ORIGINAL: quiksilver
Mine don't shoot any different whether the feathers are soaked, versus when they're dry. I put that powder stuff on them - but it wears off, and they wind up getting drenched anyway, from time to time.
Go soak one down and shoot it. See for yourself. It won't hurt anything.
I have tried it and up to 25 yards or so, I agree. But arrowflight is definatley changed beyond with broadheads. And they won't bounce back in shape easily or at all.