He also does a good job demonstrating and comparing the wrong thing. A lot of times someone will just be like "OK, do what Pujols does." I mean, that's only kind of helpful, right? Antonelli does a nice job explaining HOW and also what it looks like when you're doing it wrong/the opposite way.
I think this is most helpful when working with really raw players. I feel I can show my players the Antonelli videos and stop it at points and say "this is what it looks like when you swing" and then let him explain those differences better than I can.