bbscout:
I don't want to belabor this, which I can see is exactly what I am doing.
However, I will not argue against learning anything properly. I clearly did not when I was young. But neither did any of my friends, and some of them went on to play at a high level, including professional baseball and the Big Leagues. They undoubtedly did it the way you described -- by watching high-level guys and then emulating them.
I will add that with all that I have learned as an adult from the guys working with my sons (Brian Harper, Jim Lefebvre, Ken Phelps, Robin Yount, Lou Klimchock, Tommy Jones, R.J. Harrison), I actually have better mechanics today than I have ever had before.
But, as an example, what Calloway has described is all well and good. For a 10 year old, though, that, in my opinion, is way more than is needed and still won't result in the boy advancing behind his inherent talent. He might maximize it, or he might just tire of baseball, but he won't get to the next level without the talent.
And, to repeat myself, I have never heard any of these guys use the word rotational. They might be teaching it, but they sure aren't talking about it. The video is used from time-to-time, but that is mostly determined by availability and surely is more and more important as you move up the ladder.
Strong hands, balance, bat speed and vision are the key. Beyond that, it gets over complicated. "I'm a simple man, Jim, and it's a simple game. You just go out and play and figure a lot of this out on your own." That quote came from an assistant scouting director for a Major League team just a few minutes ago. I asked him if I was misguided on this view. Take it for what it is worth.
Work hard at the game, have fun, get good coaching to be sure, and then let your talent take you as far as it can and then a little further.