As a long time cat sailor and long time lurker on this site, I wanted to give my history on one design vs open class. Long ago, when Hobie 16's ruled the world, you either worked your way up through "C" fleet to "B" fleet then got your butt handed to you in "A" fleet, or you learned to play golf. Working you way thru the fleets meant being on time for starts, knowing the right of of the line, which side of the course was favored, what the tide was doing, staying for the whole regatta, ect. To me, open class was for people who liked to tinker, play with their boats on the beach, complain about how someone else's boat performs better in certain conditions, ect. I have to agree with Mary, et al. that formula/onedesign eliminates all those excuses and promotes what the sport is supposed to be all about.