My advice:
If you're done passing down the family's precious DNA, have a nice cocktail of
DEET mixed with
Flor de Cana Rum.
DEET works and it has been proven to do so.
Apply DEET often and liberally. No, it has
never been scientifically proven to affect the reef, but shower it off just before you dive~ why not?
The other remedies, potions and patches might or might not, depending on
which witch doctor you're believing this week. Simply not proven effective by anyone. I've seen flea collars used as anklets~ it attracted the resort dog checking for new meat and gave the gal kind of a tropical-punk look. Those electronic gadgets with the ultrasonic shield? Pisses off the bats and wastes batteries.
Kind of like the old local remedy of slathering yourself with coconut oil
This was also some sort of party lubricant, much like the aforementioned Flor de Cana Rum.
Has anyone tried a BP/W? They seem to be the cure-all for everything.
Very seldom seen on Roatan. Might have to check that out. Add pony tanks and can lights to the list.
Split fins.
That's it. (Most of us are already old-timey Moffers and that aint workin')
Don... we did use dryer sheet and they seemed to work some with the sand gnats here. I think they are worse here than in Roatan if that is possible.
No, that is
not possible.

Roatan has
the best sand flies. Try stitching the dryer sheets into some sort of
natty sweater. Get it? "
natty"

Some people just use them as underarm pads. A very nice look.
If you really want to know if SSS, B1, Garlic, Snake oil, or iguana sperm repel the bugs then just try it.
I've oiled a few snakes in my day, but the hard part is coaxing an iguana to contribute.
Looking at the toxic ingredients involved, perhaps they could be effective on some insects, but with what complications...?
Don, as always, you share a lot of good research, but did you ever find out what they spray on the beach and decks for the bugs every morning at the resort that keeps y'all so bug-free at FIBR? Next visit, take a read at the can.
(I can hardly even say dichlorodiphenyltrichloroethane, much less spell it)
Worry about the big stuff, drink the DEET... or try the handy three pack of the once-a-week dose in:doctor:suppository form- available at MallWart.
(And as I have said before, if that fails: Nasonex dabbed on the bite)