This is the guy who mounted a pulse jet on a bicycle. He's done some very interesting projects. Mostly ones I'm glad are an ocean removed from where I live, but still, very interesting.
If I were going to make something like his knife belt, I would definitely put a stop on the hinges to be absolutely sure that the knives can't come up to higher than horizontal. I think it would be pretty ugly if, for some reason, one of them flipped all the way up.