@ 45' wll, my theoretical hull speed is 8.99 knots. We've done 11 knots plus repeatedly and over 12 knots now and then BEATING, not surfing in any way or shape, and that's well reefed, not pushing or racing. I guess my GPS lies a lot! However, I have heard tales of Clipper Ships that have so far exceeded their hull speed that they have literally sailed themselves under and been lost. But of course, that's downwind.