I agree 100% FP, in regard to where the term originates from. However the "down to" the best hitters demo and talk about is completely opposite of the action of turning the barrel. So if they never heard that term before I would expect at least to see it during the demos and during their drills. I know I mentioned it previously in my post that they don't talk about TTB, however I am more interested in what they talk about, and they talk about "down to" a lot. Obviously there are missing components in their demos and that's where my interest is, what's missing? What components paired with "down to" composes a major league swing.
I would to hear them talk more about proper sequence and posture
Pros also talk about "palm up" quite a bit, which is very similar to what I consider TTB. When you watch their demos of "down to", I rarely see any palms facing up. But in their game swings, I do.