BTW: Steve Englishbey is a drummer and will chew your ear off about music and baseball so watch out...
He also lives in Texas (Houston) and was a 1st round draft MLB pick of the Houston Astros for what it's worth...
There are 2 Englishbey videos but the videos themselves aren't really the point (the videos are actually full of information but weak from a production standpoint). It is more of a "system" refined from other rotational hitting instructors, sports physiology and kinesiology, video motion analysis of YOUR kids swing, and all kinds of other stuff thrown into some "norms" that all "high level" hitters exhibit. He gives you TONS on very specific drills and is extremely active on the forum (i.e. continuous feedback, not just a "watch once and done" approach).
It is critical to also understand that the Englishbey stuff requires that YOU participate and learn in order to be your sons coach. You can't just plop Little Johnny on the couch in front of the video and expect anything to happen, just as you can't hand a guitar to a kid and expect him to start channelling Django Reinhardt right away. If you want to learn about hitting and can commit to spending the time to studying and then working with your kid, I have found none better than Englishbey (and I have a closet full of hitting videos to prove it).