I was watching this video of the American Magic training boat. This is the boat being used to train for the AC75 foiling monohulls being used in the next America's Cup. This boat is an engineering marvel, I can't imagine the hours going into the AC75 design and development. The thing that really struck me was how loose the foot of the main is. This seems to be the norm for them at all points of sail, even when the boom is on center-line - look at around 3:45 in the video. Makes me re-think mainsail trim. Also, watch how much the traveler moves, constant trimming.
Anyway, these are very impressive boats and sailors. Should be a fun event when they scale up to 75 feet.