I notice that frequently when people are hitting on the heavy bag, between shots and combinations they tend to touch the bag. Not without purpose; it seems mainly to stop the bag from swinging around. I suppose early on that's troublesome, and it's good to have a partner sometimes to minimize the swing. But eventually I really think people should stop that stuff. When you're in the ring with an opponent, they certainly will be moving; it helps to get used to that. If your footwork is good, then you should have no trouble adjusting yourself to the bag. The nice thing about a bag moving as opposed to a person also is that you can predict where the bag will go because it is tethered. This is just a small thing that always got me, i'll see a guy throw a nice combination, reset, and then hold the bag so it stops moving.