This is an old topic. Most swimmers I know appear to believe that shaving definitely produces a speed gain. I've always been skeptical. I figure that the "psych" factor of a big meet combined with a taper more than swamps any possible gain from tapering.
Well I just bumped into this video:
www.youtube.com/watch
It seems that for cycling at least, the speed gain from shaving is very considerable. Given that water is much more viscous than air, it would seem reasonable to conclude that the effect is even greater for swimmers.
