Tornado Alive recently stated in another thread in another forum (SA), that with the use of a transom foot strap and a chicken line he has never stuffed his Capricorn down wind, so they can't be that bad.
You can PP anything if you try hard enough. I've sailed with Capricorns since the first day they were launched and seen plenty of nose dives. Are they any better/worse than any other boat??? I don't think so.
IMHO the major reason why the winner is a Hobie/Cap/Infusion these days is the sailors ability and maybe 10 - 15% the boats being suited to the particular conditions of the day.
Tiger Mike