There was a guy at my gym tonight benching, but he was only moving the bar about 5 or 6 inches up and down. He had short arms, but he wasn't even coming close to a full range of motion. He was deisel as hell, so I figure he must know what he's doing. But what purpose would that serve? I've seen alot of guys doing exercises like this. Is that the way you're supposed to bench or what?