Mikey Garcia hitting the bag like a welterweight George Foreman

I've read that when Liston whaled on a heavy bag while some poor fool held it, the intent was to show how hard he hit.... while distracting from the fact that his legs were dead and he couldn't move good.

When Foreman did , everyone was amazed by his power and forgot that he didn't fight smart.

Garcia is moving up to fight a big strong guy that everyone feels he is not going to be able to hurt. So he made a video showing him working on punching real hard.

You have to understand that any video released to the public of a fighter training for a fight, it is pure propaganda. The chances of a camp revealing what they are actually working on and how they are doing it is very small.