Valid point. I guess I have a different though on the whole thing. It simply depends on the situation. If I am pulling a knife on someone, it is because I believe my life is in danger, and I am prepared to do whatever I need to to prevent that threat. Be that using a blade, or breaking his knee, it's hard to say "in this situation I'd do this" (which I guess I sort of did above)...
I guess all I'm trying to say is this...the spydie in your pocket does not make you invincible, any more than a gun. You have to know what you're doing. Same with hand-to hand. Whatever you have and are good at, use it if you have to.