The only time I have capsized in the short time that I have been sailing cats was a pitchpole (flipped forward). I think I hit one of the bridle wires on my trajectory because I had 2 sprained fingers. And yes, this did seem like 20 to 0 in an unexpected (and quite dramatic) instant. But like I said I've only been sailing for a short while and had I been more experienced, I may have seen warning signs. On the other hand, I've heard that more experience leads to pushing the boat harder which leads to more capsizes! I guess you just get better at crashing without injury.