I like your train of thought for going upwind but what happens to the mainsail foil shape going downwind, it could produce such lift that your VMG would go out the window? Anyway, 'I know nothin' and I'm sure we'd like see one of your prototypes soon. Maybe the Global Challenge for instance <img src="http://www.catsailor.com/forums/images/graemlins/grin.gif" alt="" />