[/quote]
I wonder if that is the variance allowance that was put in the original rules when the requirement was that the catamaran for the Olympics would have to be able to be home-built. Obviously, it would be more difficult to build a boat in your garage to the same tolerances as in Marstrom's factory. So maybe they allowed a little slack in the rules for the people who could not get their plywood bent quite to the right shape? [/quote]

That may be, but part of the reason truly was to allow differences in hull shape. Ie, Yankee Laminates Tornados had a finer bow entry and was pushed to the maximum tolerances at the deck line. This gave the hulls at the bow more volume with the thought being that it would create greater bouyancy. So you basically had four different designs, even though minor between Marstom, Sailcraft of Canada, Reg White and Yankee Laminates. It is too bad that the home built loophole has been closed for the Tornado Association. I think that I built one of the last allowed home-built Tornados.