The youngster in the second video needs a haircut, other than that, he’s quick - I’ll give him that.
I’ll assume that the second video is the “after”. I’ll also assume that I’m looking at the same pitcher.
In the second video he is a little bigger upper body wise, at least that’s what I see. And by all accounts, I think the objective of this review is to give some sort of opinion on the finished product - second video.
For what it’s worth:
I see high maintenance issues later on - shoulders/neck
I see a lot of wasted motion going up, instead of forward.
I see a predictable pitcher who’ll get hit, and hit often, after one inning.
I see a very limited inventory based on a limited foundation - quickness.
( I can expand on that last observation in more detail if you’d like.)
I see in the first video someone marking off a place on the stride. Then, the second video doesn’t reference that attention getter. Not that I could see from the angle and view of the camera.
I as a pitching coach could work with the very first youngster and develop a program guy. The second video shows me a youngster that’s pretty much set in concrete with how and whatever he’s trying to do.
Now I’m not saying that I haven’t worked with pitchers, like in the second video, in fact I have. Their problem was always one of sustained energy. After a few batters, their predictability was a given, their energy level diminished over time (eight batters on average), and their control left a lot to be desired. To make matters even worse, after one or two showings, the scouting usually had these guys pegged.