What if the winglets lead to some other new problem! ?

Also consider that even if they were perfect right out of the box, they would certainly change the way the boat handles on all angles of sail. If I had been training and testing and working all of this time, I might be pretty upset at some new forced change to the boat that caused me to go back to square 1.

These guys and girls can get this boat to turn around A-mark just fine. They're all just pushing it at the limit of what it can handle and we're seeing those that are finding where that limit is. I mean, seriously, they could raise the leeward board or some other means to reduce the pitching moment if they really needed to.