If there isn't already a law against the maximum approach velocity of one's hand into a handshake, there ought to be one. And guys, if you find your arm-shoulder swinging by more than a couple of degrees to the right just before a handshake, you are probably overdoing it.
BTW, anyone remember the name of the comicbook detective with the bone-crushing handshake? Rip Kirby, was it? It was definitely one of those 1940s-style noirish strips.