One of the things that I have wondered about while watching all of these foiling craft is the effect of foiling on windward performance. When these boats are riding along, at times nearly the entire centerboard is out of the water. That's got to just about kill all of the lateral resistance. This is evident in the 18skiff video, when they get going, the boat heels to windward and the guys come running in off the wing. I guess it's part of the technique where the skipper trys to keep the hull just above the water surface, but it seems like they might benefit from putting more board below the foil, or moving the foil up higer on the board.

sm