OK, I'm receptive to this argument. Make me believe that as a large male (6'3", 210lbs) that this kind of wetsuit will make enough difference in propulsion efficiency to make it worth me purchasing it. I dive wet all the time, but mine is a traditional wetsuit. Even my 3mm semi-dry that I use in warm water works fine by me. I think that I can overcome any efficiency due to slickness simply with my practical, forceful kick, but I'm open to considering the math and physics that disproves this. Having said that, I'm not interested in micro-efficiency.
Having said that, let me put this in perspective. I was a competitive swimmer in high school and college. I've done the shaving, oiling, and special suits to minimize surface friction for the purpose of streamlining. And although it can improve times by hundredths, even tenths of seconds, this is immaterial in the application of diving. Compared to a swimmer, you are a giant cow as a diver. You bulldoze through the water, rather than streamline through it like a swimmer. So, ultimately, I can't see the surface friction of a particular suit making any practical difference to me. As said above, if you can show me how significantly my air consumption, based on reduced effort, will decrease, I'm all ears.
OK, first, you brought up an EXCELLENT POINT... the swimming drag issue....skin, or oiled skin, etc....the thing is, skin itself is pretty slick....trying to get less drag than skin gets you diminishing returns fast.
BUT..try swimming competitively against your buddies while you wear a big floppy flannel shirt, and some big baggy trousers. I think swimmers you could normally destroy, would be killing you
This is the issue with wetsuits and dry suits....the dry suits are like the baggy clothing, the wetsuits more like the skin....particularly the slick free dive suits....there are several semi-dry suits that are really wetsuits ( by texture and drag), and that are not catastrophically slower than a slick wetsuit for most "dive missions" I could imagine....while the dry suits WOULD BE CATASTROPHICALLY TOO SLOW for many, many dive missions I have been on in the past, and will be on in the future.
I have a very custom DUI TLS 350....and I have used it in the incoming tidal current at the BHB ( which is too strong for many scuba divers to swim against)....found I could beat the current, but that it was big work...then got out, switched to my free dive suit, and found the same current was insignificant to me--I would still have to crank up some speed, but it was easy speed, and I could even kick and glide--which is impossible with the dry suit....Add to that probably 50 to 70 dives in winter time with the Dry suit , on dives I have done many hundreds of times with slick wetsuits --and the dry suit effort is obnoxious....and I can't follow the marine life nearly as well...And breathing rate goes up, bottom time goes down.
To me, the TLS350 is crap...for the diving I do....If I was absolutely not going to dive tech any more, I would GIVE it away to someone, or sell it....or just throw it out......but...I will likely still do tech dives for several more years, and for this I need the dry suit until there is better perfection of electrical heated undergarments, or of a better grade of heat pacs and hi tech slick fabric outers with better thermal insulation. This technology will be here soon enough....and the dry suits will be garbage --for me--when this happens. My wife will use her TLS350 for macro photography at the BHB Marine Park, for 4 to 6 hour long dives ( in less than 18 feet of water), and where she and her buddies are practically motionless for 30 minutes at a time....To me, this is not diving...I am happy for Sandra that she loves this, but it is an entirely different sport or activity than what I like....My thing is shooting video of big marine life. Everyone needs to have a mission--I guess the dry suit crowd just pick the slow missions
Using a drysuit is like cutting your fins in half, then telling everyone you like diving better this way--and that no one needs to go faster than you can swim with your fins cut in half!!!
