IO540 - Not in the (open) boats I used to sail in. Granted, you do have more space in a boat, but in all of the aircraft I've flown in so far, the charts have never blown out of my hands or been soaked with rain. The only time I had a proper nav table to work on (rented yacht on a school trip), I tried to do the nav but I got seasick before finishing all the calculations. I was back on top in the nick of time... And I was the best of the lot. The girls (in sailing suits, not swimsuits) didn't even dare to come down.
tmmorris - I agree. The one in sixth rule, "I follow roads", and the length of my thumb from nail to first joint is 10 miles or five minutes (@ 115 knots). Close enough.