"Drifting" seems like a reasonable term... As soon as the ball leaves the pitcher's hand, the hitter is immediately starting to process information. That process continues throughout much of the swing. Notice the very subtle differences between these two clips. Personally, I do not see any "slop" and I definitely don't see "DBSF".
During this move-out I don't see 'drift' I see *tip* (or in less obvious tip cases, I see or feel *pressure*) which is critical PART of using the hands to work the handle to turn the barrel, ie you don't just TTB in one direction you ideally tip and (reverse it) rip, all around a tight hand pivot point. I think slowing the video down and looking for a forward drift or independent-of-the-hands elbow slot is really working hard to create a counter-narrative to TTB and missing the main point -- the hands are live, independent and working the barrel as quickly and tightly as possible to turn the barrel behind the ball. I work elbows as a 'side-teach' -- not at all if they are working correctly, a little bit of instruction if they get lost on certain pitch locations such as high. But the action and sensor is at the hands....at least IMHO (and that's just talking about TTB as an isolated move, which it isn't, it's blended with coil and stretch and ultimately *GO*).
