Messages

1

Random / Re: Some days technology just fucks with you

« on: April 04, 2024, 07:47:32 AM »

Interesting thread, I work for a small privately held company that designs and manufactures scientific instrumentation, and our President (73 years old) is all in on AI, VR + AR thinking that it is the future.   I've worked with our service engineers on the VR + AR projects related to supporting our International Service centers and found this technology to be a huge benefit in diagnosing, troubleshooting and repair as long as one party involved is willing to sacrifice some sleep due to time differences between ASEA and Asia.   We usually alternate on who has to be up at 6am or midnight local time so that the other can be available at 6pm or noon.

What I don't like is AI as I find it totally useless for my field and a huge time waster.   Why does it waste my time?  Our president insists on asking all different versions of Chat based AI questions related to our industry in an attempt to create marketing content showing our companies superiority of design compared to our competitors.   What usually happens is that ChatGP give the opposite answer than what is expected, and I end up having to either prove ChatGP wrong, educate our president on the concepts that "words have meanings" and help him structure directed questions rather than vague questions.  This can entail me having to write a several page responses with 1. the correct answer, and 2. a forensic search on where the incorrect information originated, (usually from a college science student blog, or a competitors marketing,

Personally, I don't use any AI since all information relevant to my role ensuring that our instrumention and software reporting conform to all national and international conventions such as ISO, ASTM, DIN,BAM, SAE, CIE, USP, NF, CP, JP, ANSI, ISEA, AOCS and about 100 other standards organizations, including the major publishers such as Wiley Inter-Science.   All of these organizations tightly control their content behind firewalls, they have all added verbiage such as this; Artificial Intelligence Policy: ASTM International prohibits the entry of ASTM standards and related ASTM intellectual property (“ASTM IP”) into any form of Artificial Intelligence (AI) tools, such as ChatGPT. Additionally, creating derivatives of ASTM IP using AI is also prohibited without express written permission from ASTM’s President. In the case of such use, ASTM will suspend a licensee’s access to ASTM IP, and further legal action will be considered." to their websites.

What happens whenever our president uses Chat he gets bot answers that are only based on data from the public domain and zero input from the scientific community resulting in about 30% of answers being so incorrect as to be laughable., 30% to being circular nonsense and 40% to being marketing based responses.   

Since I hope to 90% retire in the next year and earn a little money on the side writing technical papers for publication behind the firewall I hope to continue to earn some easy income factchecking AI answers for a few years longer.    For laughs I may start my own blog and purposely post slightly misleading content just to have fun and see if it turns up in Chat GTP responses.  Lol

2

Downwind and Racing / Re: Anybody into SUP Racing? Downwind/Flat?

« on: December 25, 2022, 11:43:50 AM »

I've been windsurfing for the past 40 years, can't give up a good side off wave session, living on the  Hatteras Island I can ride Port or Starboard on a wave.  Started SUPing about 10 years ago, began with an inflatable on the lakes in the Northern VA area where I currently live, but was soon SUP surfing during no wind days when back on Hatteras Island.  4 years ago I got into Foil Windsurfing and then WindsurfWaveFoiling (WWF).   In the Annapolis, MD to Cape Hatteras area there are still a number of SUP races each year and I regularly compete in at least 3  year since my first event not soon after I started.    Chesapeake Bay Bridge Challenge is a 300+ competitor event, EYC/EOM Annapolis is about 100 competitors,  Hatteras Island Cancer Foundation Paddle Palooza is about 40.   All these events were bigger about 5 years ago, and it seems like a reunion each year as familiar faces keep returning.  There are still events on the James, Virginia Beach/Hamptons Roads area, Wilmington, Dewey Beach area, etc.    My best year I entered about 7 events, now just the three closest to me.

I still work a full time job, so time at my Hatteras home is limited to only 8 to 12 twelve weeks a year (thanks Covid for normalizing Remote work, just wish I could do it more).   I find it best to keep doing the best activity for the conditions instead of abandoning one sport to pursue another.   It keeps my shed so packed with boards, sails, gear that I can barely move around, but if it's blowing 30+ nothing beats a slalom board and 5.0 doing 3 mile long reaches at 25mph, jumping every piece of chop, the same as if it's sunny and offshore with a a 3 foot swell, might be a morning high tide 3 mile paddle up to the pier and back until the afternoon when lazy thigh to waist high peelers show up, or a perfect wavesailing or foil session.
SUP racing means couch surfing at friends homes, getting up early for an 8 or 9am start and off the water an hour or so later depending on distance. It's the best excuse in the world for a frothy draft beer at 11am, before lunch followed by awards, followed by a band playing until dinner.   I'm not ready to any of it up yet.   Maybe when I retire I'll quit windsurfing, SUP racing, wavesailing, and WWF and just focus on one sport.  Haha.

3

Gear Talk / Re: Sunova Kanga 10' fin suggestions needed

« on: September 07, 2022, 12:41:56 PM »

Thanks for the reply.   I'll be slowly heading out only in smaller surf these next few weeks as my Hip rehab progresses so I'll try the Rasta HC's for now and if I find them too loose then go  for the Sunova set.  I've found the Speeed to be perfect with the stock fins which are definately bigger than the Rasta HC's.   I need to get my activity level back up so I can loose 15lbs and get back down to 235, which seemed to be a good weight for the Speeed.

PS    Jimmy wants to know when you're going to visit VB + HI with your van full of boards.  He's still in the market, but would really like to try before he buys.   

4

Gear Talk / Sunova Kanga 10' fin suggestions needed

« on: September 06, 2022, 12:39:30 PM »

I'm the new owner of a previously owned Sunova Kanga 10' x 35 1/4" that came with Futures Rasta HC Quad fins.  These measure about 4" and 3.5' and seem to look small.   I own a Sunova Speeed 9'5" with stock fins, tri setup I think all three are 4.75" or 5".    I'm currently at nine weeks since Total Hip replacement and bought the Kanga just to have something stable to paddle around while completing my rehab.   I got in an hour or so at high tide yesterday, as the swell from Earl here on Hatteras Island is picking up and I was afraid to try paddling out through breaking waves.  The board seemed to track fine over the rolling swell, so I don't have feedback other than the setup looks small.   The Sunova site has Futures fins branded GR for Genration but don't list size or area.

Anyone have any experiance with this board?

5

Wingsurfing, Windfoiling, Wingfoiling, Wing SUP / Re: Knee pads

« on: January 23, 2022, 10:30:30 AM »

I've found that any inexpensive knee brace with a patellar support usually consists of a donut of padding around the kneecap.  These are much lighter than traditional kneepads, volleyball pads, etc.  They usually have some velco straps to keep the brace in place and provide compression and support in addition to protection.  They drain water well due to the hole in the donut and should provide more than enough protection for most activity.

6

Wingsurfing, Windfoiling, Wingfoiling, Wing SUP / Re: Any good spots on the sound in OBX for foiling?

« on: October 18, 2021, 03:24:25 PM »

I foiled Canadian Hole 8 out of the last ten days.  I'm pretty much off the grid when down there so I'm just seeing this message. Pretty decent crowd this week, and nearly every night due to the good conditions Matt from Real showed up and put on a jumping show on his potato chip thin strapped board.   When he starts pumping his wing he's sunk nearly waist deep.   I think his board is about 2 1/2" inches thick.   Always amazing to watch him pump his way up on foil.   Interesting to see his straps are unidirectional, he rides both tacks with the same stance.   My guess is he's getting the bottom of his board about 5' to 6' in the air as his foil is about 3' above the water when he jumps.

Early in the week was great due all the west in the wind which forces water into the bight and increases the depth, prior to Sat 10/9 it was predominantly E winds which made it very shallow.   With a 60cm or 71cm mast on those NW and SW days you could ride about 1 mile out from the beach.   Basically just west of the Hole heading straight out from the beach  the water is about 3' -4' deep for about 20 yards.   Just don't fall in there you'll need to walk to get going again.   Once past that area water is 4 to 6 feet for a huge area, stay away from the Duck blinks, there are all built in shallow water areas.  If you ride a 80cm + mast then staying in the Hole or the channel that runs from the Hole to Kite Point parallel to Hwy12 is a must, except in straight West winds when water levels increase, especially if it is a multi day blow.   Between the new moon 10 days ago and the stalled front offshore, the Hole was the perfect spot on the island.

There's miles of deep water just behind Brigands Bay on NW, but unless you know someone you'd need to rent a house to access that area.

Kiter's always get the stink eye if they land there.   Earlier in the summer a kiter, locals call them jigglers, put his kite into the  power lines.   Knocked out electricity from Avon south to Buxton for about 4 hours, great for the environment to have 1000 HVAC systems shut down on a summer day.   Cape Hatteras electric just uses a sharp knife to remove the kite and lines, user is responsible for discarding the shredded  fabric.   CHEC then bills kiter for the service of re-energizing the circuit.  NPS gives a ticket which will require a court appearance in Federal Court for trying to  land a kite within 50 meters of the high power lines, judge gets to set the fine.    Net-Net, I have no issue with any kiter who has a spare $5000 to gamble on being able to put down their kite without inconveniencing several thousand visitors, especially when the NPS built a parking lot at kite point that is several hundred meters from the power lines.

7

Foil SUP / Re: Build: Deep Tuttle to Plate Adapter

« on: January 09, 2021, 04:05:40 PM »

I converted an AHD Formula Diamond 95 to WWF by adding a GoFoil Tuttle box about 4 inches in front of the existing Deep Tuttle box.   I was disappointed that the GoFoil box dimensions we quite a bit smaller than the design dimensions shown in the attachment.   It was about 2mm narrower than the Tuttle adapter that came with my Slingshot foil.  It was super tight when I tried to insert either a TrueAmes windsurf fin or the Powerplate tuttle adapter.  For those it was about a 1mm difference.   
Since I didn't want to sand the anodizing off of the Slingshot aluminum tuttle head, I created a sanding block that I could glue sheets of 60 grit and used that to enlarge the interior of the GoFoil box.

8

General Discussion / Re: Island Beach State Park NJ SUP surfing ban

« on: July 19, 2020, 09:26:39 AM »

I've been away from that area for 23 years.  I looked up the IBSP current rules and they show that Sailboarding and Surfing are only allowed in the area directly south of the bathing beach.  This might be a tough fight as technically no one is allowed in the water outside of the lifeguarded area.   Asking surfers to support your effort may only result in them also being banned from the water outside the designated area.   My take would be work on getting SUP added to the Sailboarding and Surfing area.  This would "make SUP an official activity" and give Park Rangers the discretion to allow it in areas other than the designated area.   
Writing to Surfrider, Surfshops, NJ Senators, Governor is a scattershot method.   Best to use science and existing Law, save the petitions for last as they will have the least effect IMHO.   Create a simple chart showing the Coast Guard classification of Surfboard, Sailboard, Kayak, Canoe.   The former are allowed activities, the latter are banned activities.   Show how the SUP aligns with the allowed activity closer than the banner activity.   This would have to conveyed to NJDEP as they make the rules.   Having a friendly politician can help to get the audience with NJDEP.     Good Luck.

9

General Discussion / Re: Island Beach State Park NJ SUP surfing ban

« on: July 18, 2020, 01:26:29 PM »

As a past president of the New Jersey Windsurfing Association NJWA (1994-1997) we lobbied the state for ocean windsurfing access at IBSP.  Our coalition consisted of  the NJWA (which had two Olympic hopefuls at the time, 200+ members and the largest windsurf regatta schedule in the USA) we had many small business owners (employing 100's in Ocean and Monmouth Counties), doctors and lawyers helped with our petitions, it was a well organized effort.   

 At that time if you anchored in Tices Shoals and walked over with a long surfboard or windsurfer there was a good chance of being asked to leave the water, fishing only.   If you launched a waveboard and  in the ocean in  Berkley Twp at 24th and then sailed upwind to the surf breaks inside the park limits the rangers would try to whistle you in and then tell you the that state had jurisdiction over the sand under the water out for three miles and that windsurfing and surfing were banned inside park limits.   The State Park service finally relented to our request and formally allowed oceanside windsurfing a IBSP in a fashion so that they could say they compromised to our request and met us in the middle.   Of course after we read all the rules allowing us access no one was actually able to take advantage of it.   We we blindsided by how well they listened to our requests, read our position and then figured out how to grant approval in a fashion as to make surfsailing at IBSP impossible.    To begin, we could only access the water from the south end of the main bathing area parking lots.  Could only surfsail when the beach was open to swimming, had to stay in a 50 yard wide area that began at the south end of the bathing area and continued south. If we sailed into the swimming area we could be whistled out of the water and made to leave the beach for the remainder of the day.    To begin, the primary winds in the summer were southerly thermals in the 15 to 20 range.  By giving us a very small upwind section of the beach it was near impossible to stay out of the swimming area.  When the wind was good and the waves were good the beach was red flagged to swimming so no sailing.   No sailing once the lifeguards went off duty.    They had won, to the general public they could announce they had granted access to the NJWA request for use of the state beach, to the actual users they made the rules so onerous as to make it impossible to actually use the beach.    That was a year or so of time petitioning, answering requests, public meetings fully wasted. 
 
Maybe, possibly these Windsurf Access rules are still on the books and could be gently modified to allow SUSing at the south end of the bathing beaches in the 50 yard wide corridor that was allocated for Windsurf wavesailing.  It might be worth spending the time to research as obscure rules often aren't rescinded, as the public effort to remove them might be as onerous as it was to get them enacted.

In hindsight I believe that the lobbyists for the NJ Beach Fishing or Beach Buggy, not sure of the exact name, was behind the scenes doing everything in their power to deny us access to what they perceived as their beaches.  Then when told by the state that our access could not be denied they poured through our written requests and maps to give us everything we has said was unsuitable.    We specifically asked for 100 yards of beach downwind of the swimming area. We outlined how unlike surfers we could regularly ride waves for 30 to 50 yards, then slowly sail back up wind.  We noted if we fell while waveriding, or the wind dropped we could easily drift 50 yards downwind until we got our gear back into sailing position to head back upwind.  We requested the downwind beach so that in the event of lost/broken gear or wind drop there was no chance that we would drift into the swimming area.   The state used this rationale against us, saying that Lifeguards could not be responsible for a rescue if we were outside of the designated surfsaiing area, they could not justify adding lifeguards to monitor an additional 100 yards of beach for an activity that was dependant on the weather.  They put us upwind so that in the event of gear breakage or separation from gear we would drift into the lifeguard area not away from it.   They said it was our responsibility to not drift into the swimming area, not the lifeguards responsibility to make a rescue 100 yards down the beach.   But if we ended up in the swimming area we needed to leave the beach.

Two years later I sold by Toms River house, moved to Hatteras Island and didn't look back for 20 years.   I didn't sail/surf/sup  NJ until last summer when I took advantage of LBT's surf between the flags trial.   If not for CoVID-19 I probably would have been back on LBI earlier this summer.   IBSP is a beautiful spot but until the Fishing Lobby can be broken it will stay inaccessible to surf/sup/sailers forever.  For now if I do visit NJ in the summer then LBI or Absecon Inlet will be the destination.

10

Classifieds / Re: Riptide side fins

« on: June 13, 2020, 06:18:35 PM »

Are these still available?

11

Random / Re: On the plus side...

« on: April 15, 2020, 07:03:46 AM »

Viewing the outdoor shower creation has been chuckling thinking about the reply that will never happen due to wardoggies retirement.  Imagine a followup thread filled with the claim that wardog was actually the first one to build an outdoor shower out his gear, then flood the post with photos of his SUP boards as shower backstops,  used his big wave leashes as clotheslines, had sidebite waveweed fins mounted horizontally as soap shelves, etc.   

12

Random / Re: If you don not have cable at home...

« on: April 14, 2020, 11:08:58 AM »

I live within 50 miles of D.C. and have an antenna that gets about 30 channels including the national networks in HDTV. Plus when the skys are right can switch between DC stations and Baltimore stations which can allow me to choose between Redskins or Ravens games in the fall.  When Radio Shack went bankrupt a few years back I upgraded to their top of the line Antenna and paid 70% off list price. One of my best purchases ever.   When I lived in rural NC and could not access any OTA TV signals by antenna, I discovered a Government program where Satellite and Cable providers by law had to provide basic TV, e.g. National Networks ABC, NBC, CBS and PBS for 4.99/month plus installation or equipment.   Since the local cable provider wanted several hundred dollars to run a line to my house I decided to take a 140 mile round trip ride to the nearest RadioShack (boy do I miss that store) and buy a Dishnetwork receiver and LMB.   Installed myself, called Dish and it took a while to get a manager to acknowledge the 4.99/ month program existed and was in business.   Best part was when they asked me which region satellite feed did I want, Raleigh or Virginia Beach?   Having moved from NJ the thought of having my local football be either the Panthers or the Redskins, I asked if I could choose any US feed.  The answer was yes, so I picked up NYC and got my Giants games every Sunday.
I don't know if this program is still in effect, once I got the manager on the phone all he needed to verify was that my zip code was in a qualified Rural non OTA area which really just meant that the bill was sent to a qualifying zip code as there was no way for them to determine where my dish was located.     
I've never been happy with the way the networks have been able to buy Congress and have laws enacted that give them a monopoly over  airwaves that belong to all of the people, but no responsibility to reinvest profits from cable TV contracts into expanding OTA coverage for the people.   

13

Random / Re: COVID-19 Data Model Updated Daily

« on: April 14, 2020, 10:15:53 AM »

I stumbled onto this thread and started reading it in reverse when I saw the exchange above.   Is this tongue in cheek sarcasm between Admin and Beasho or do those two really not understand how accurate a 95% uncertainty level represents?  If I missed the intent I apologize in advance.   

The shaded areas that they mention in their definition currently shows a potential USA death range between 180,000 people and 30,000 people.  150,000 deaths is a huge range of uncertainty.  The quote that I had posted (pasted again below) from the IMHE sums it up nicely in terms that anyone can easily understand.  They include that definition and explanation on every one of their charts.

When I read your post it seems like you understand Uncertainty but then when you comment that 150,000 deaths is a huge range I wonder if there is complete understanding of how this data is presented.   Numbers are fun, lets play some statistics game with them.
IMHE says 30,000 to 180,000 with 95% uncertainty, this is not a Gaussian distribution since the number of deaths can't be negative, but the projection is in the second third of the projection, or fairly weighted.   The best part of uncertainty is that there is an equal probability of any outcome in the model.,   e.g unlike Vegas where the house has the advantage on the roulette wheel with the 0 and 00 spaces, the IMHE model gives an equal chance to every value between 30,000 and 180,000.   We can be optimists or pessimists when viewing these projects but the math says either outcome or any in-between outcome is equally likely.

Let's use a real number set from https://covid19.healthdata.org/united-states-of-america  projected for May 1

51,405 deaths with 95% uncertainty that this number will be between  28,282 and 112,584   
 
lets do a simple conversion to 99.7%

51,405 deaths with 99.7% uncertainty that this number will be between 16,721 and 153,047

the last conversion would be for 68%

51,405 deaths with 68% uncertainty that this number will be between 40,000 and 60,000  ( I rounded here for simplicity)

Again equal likelihood based on stated uncertainty of any value within the range occurring.  So since today's actual reported death toll is 22,000 the model is flawed as the 99.7% estimate is low.  One would expect that actual value would not be lower than the estimated value. My guess is that as we progress in time that IMHE will be modifying their estimates as new data is collected.     Since I'm a scientist in the spectroscopy field and not infectious diseases I need to find some perspective to determine if these uncertainties are in fact "quite huge" or actually normal.   Looking at the CDC website and their projected death rate for Influenza in the USA for Winter/Spring 2019/2020 they listed an estimate of 24,000 to 62,000 deaths with a 95% uncertainty were expected.   They note that these numbers were generated from a pool of data that represents 8.5% of the US population (~27 million people)   So the CDC has a sample pool that is many magnitudes larger than the world wide Covid19 pool and has been studying this disease extensively for the past 60 years and the best guess of deaths has a  range of 38,000.   For a novel virus like SARS V2 with near zero historical references, a death estimate with a range of 150,000 or only 3x that of  one of the most highly studies infectious diseases in the world does not seem unreasonably large.

Now take into account China under reported deaths, rumors are putting the actual Chinese death toll between 20,000 and 1,000,000 and our estimates don't seem out of line.  Then consider that if 62,000 Americans had died of the flu in the period from November to today, not a single bit of the economy would have been shuttered, I'd be competing in the OBX-Wind Long Distance and Slalom races this week, and life would be going on as normal, instead of social distancing on the farm for the past two + weeks.   Current flu deaths for USA are in the 23,000 range and current CoVID19 in the 22,000 range, for a total of 45,000 which is approximately the Mid Point of the CDC Flu estimate ( 43,000 +/- 20,000 K=2) Every death is tragic, but in the big picture we're having a relatively mild Influenza season and must be doing something right to be keeping our CoVID19 numbers so low. 

This thread's deep analysis is what I wish I'd be viewing on the mainstream media's news reports, not something buried in a Standup zone forum.   

14

Random / Re: COVID-19 Data Model Updated Daily

« on: April 13, 2020, 07:55:16 PM »

The model presented in this tool has a 95% uncertainty interval and is represented by the shaded area(s) on each chart.[/b][/size]

This really pisses me off.  I work to make sure my reports are near 100% perfect.  There are a few small math issues with running totals and averages based upon how the data comes in but I would be willing to say my data is 98%+ accurate with regards to the source vs. 95% wrong.  Holy Moly.

Hi Beasho,

They are talking about the unreliable nature of the underlying data itself, not internal errors in their reports or math issues.  Testing data, start dates, etc.  It is a real mess.  Data is never perfect but this is really remarkably bad. 

To make that even more notable, that is without any changes to any of the parameters.  That is a different issue altogether.  Change (for instance) the value given to distancing and that would be an entirely different model snapshot.

I stumbled onto this thread and started reading it in reverse when I saw the exchange above.   Is this tongue in cheek sarcasm between Admin and Beasho or do those two really not understand how accurate a 95% uncertainty level represents?  If I missed the intent I apologize in advance.   

If for example a manufacturer said that it's new 14' Raceboard was guaranteed to have a dry weight of 14.3kg +/- 0.2kg with a 95% uncertainty then out of a production run of 100 boards the following would be true.   68 boards would weigh between 14.2 and 14.4 kg, 95 boards would weigh between 14.1 and 14.5kg and 99.7 would weigh between 14.1 and 14.5 kg.   Except for the constants of nature one would never achieve 100% accuracy.    These confidence levels or uncertainty levels only apply when the sample set is Gaussian.  In this case does the glasser use the corrrect ratio of resin to cloth?    The statement 95% uncertainty does not indicate that only 5 out of 100 boards would be in the 14.1 to 14.5 kg range.

This thread seems to be arguing, and I fully agree with argument, that Bayesian probability needs to be employed to understand this virus.   Take the simple example below;

"A patient goes to see a doctor. The doctor performs a test with 99 percent reliability--that is, 99 percent of people who are sick test positive and 99 percent of the healthy people test negative. The doctor knows that only 1 percent of the people in the country are sick. Now the question is: if the patient tests positive, what are the chances the patient is sick?"     The intuitive answer is 99 percent,

but the correct answer is 50 percent...."    Only one out of 100 patients is actually sick, the test gets every 100th result wrong.   Combine them and the risk of the getting a false result is just a coin flip.   

This virus is not killing indiscriminately, other factors are having a huge influence on the outcome of the few are carriers.   Explaining this concept to the masses is more difficult than ensuring the few who read this post understand the general terms used in typical probability statements.  We should be happy that even though these comorbidity numbers are not in the mainstream they are being published and available for anyone who searches.   We are lucky to live in a country that is so open to providing scientific results to its people via the web, even if the talking heads in the media don't take the time to report them.

15

SUP General / Re: Surfboard Leash String - what to use?

« on: May 19, 2019, 10:36:55 AM »

Little off topic but.. do you wear waist harness for surfing or for flatwater/oper water paddle?  I used waist PDF as a waist harness and found it convenient not sure if I would like in surf conditions.

For flat water I wear a waist PDF and connect the ankle strap from a coiled 8' leash around the belt.


For small surf, e.g. up to 4' faces, I guess that would be 1' Hawaiian, I use a calf harness.   When I fall I immediately fold my leg so by calf touches the back of my thigh to absorb impact of leash tug, this works well so far to date.

In bigger surf I use the waist harness.  It's basically a velcroed webbing belt that you attach to a regular surf leash by removing the alien head bolt that connects the cuff to the swivel and replacing with the waist harness.   When you fall the tug folds your body in half, but doesn't pull you under water.  It's very easy to recover from a fall and as someone who has had 5 knee operations, 4 on the left knee and 1 on the right knee it will hopefully allow me a few more years of snowboarding before I get the mechanical hinge installed.    I don't wear it all the time because it's a pain to have to clear the lease off the deck before remounting the board.   With the calf leash you can position the cord perpendicular to the board and it mostly stays there, if it rotates in line with your butt it's easy to rotate it back.   With the waist harness every fall will pull the leash directly behind you and it's a rash guard twisting mess to try and rotate it off to the side.  So when remounting the board the leash is usually lying in between your feet.   Best to push it off to the side before remounting, rather than standing a trying to kick it over or bend and move it over. 

I don't think I would trust the snap in buckle of a waist PDF to hold the force of a decent sized wave and wouldn't recommend that setup for large surf.   You could try it in the small stuff to see how the pull differs when centered at the waist.