They were reefed. If you get into a tornado like wind (With a low pressure central core lifting up the cat and the two walls of the cyclone spinning it), what do you expect to happen?

I believe a monohull would do better -- I've heard stories of monohull sailboats being hit by waterspouts and getting through them. BUT I have no objective data to show that.

As for being hit by such a fluke condition -- sometimes you number is just "up". Darwin's random selection test (if you exclude the choice of vessel) :^))))))