: I promise if you try it in a boat you're familiar with you will
: notice a difference. As for not seeing it on big time race
: boats, not sure about kayaks but on every Rolex boat I've been
: on we sanded the hull and not just the ones in the water (i.e.
: Not just to get the scum off) but boats that were hauled out
: were sanding below the waterline with 400 grit. Some use 600
: grit. Just give it a try- heck, don't you have about 100 boats
: now anyway? :-)

Thanks for the info. I have a favorite 9-mile course I can time myself with rough finish, 400 grit and maybe smoother. (If 400 grit is the answer, it won't be hard to scuff it up again.) Do you sand with the direction of the boat, cross-wise, or in random circles?!