While a bodysuit may provide a hydrodynamic advantage over bare skin, I have not yet seen a discussion regarding the additional weight of using a bodysuit. More particularly, water infiltrates the suit and remains within the suit as you swim. That is, water infiltrates the structure of the textile and also gets trapped between the suit and your skin. As you move through the water, the energy you exert also has to move the water within the suit.
Let us look at some basic math: the average body surface area for a man is 1.9 meters squared (this is from an article in Wikipedia on body surface area, BSA), which equals 19,000 cm squared. If an average of only one millimeter of water is trapped by the suit (i.e., within the structure of the textile and between the suit and your body), then a volume of 1,900 cm cubed of water is being pulled along with you.
Given that water has a mass of approximately one gram per cm cubed, this adds 1900 extra grams to your body. This translates to about 4.2 pounds of extra weight that you have to pull through the water.
The question is: would you rather have slightly better hydrodynamics or lesser weight. Personally, I'll go for the lesser weight any day. Your thoughts?
If so, I can't believe that Speedo, Tyr, etc. wouldn't be promoting the bejesus out of "EZ Swim Spray (TM)" body suit coating mist.
Oh no, they're too busy convincing you that you need to buy a brand new suit to get this water repellency back. Selling a new $300 suit is going to make them a lot more money than selling you a $9.95 bottle of Nikwax.
And you're a little confused on the shark denticles and dimples on a golf ball. What these do is trigger turbulent flow. This causes flow separation to occur farther back and this reduces the size of the wake. The net effect is to reduce drag, not increase it.
