Originally Posted by jdoggivjc 
Chop blocks or cut blocks? Big difference in legality. A cut block is when someone goes low on a player, usually around the thighs, to get a defensive player to fall down over him so the QB has more line of sight - similar to chopping down a forest. A chop block is when someone engages the defender up high, followed by someone engaging that defender low, usually around the knees. This is a very dirty block, can blow out the defender's knees, and will **** a defense off to no end.
Blocking was very different in the leather helmet days. You could block below the waist downfield and even on special teams as long as you didn't clip or block from behind. You could cut, chop, hi/low, whatever. The big difference was that you could not use your hands at all even between the shoulder pads. You basically had to keep a closed fist so it was harder to control the defender's upper body while a teammate hit the guy low. The typical blocks were either shoulder or cross body which minimized the need for a more elaborate helmet/facemask.
