Yes a typo. 83 was his velo at 16. At 22 he is still only at 85-86 even though he has really gotten stronger. Added 25lbs of muscle.
I disagree with the comment on his hear moving out of the way. It shouldn't pull off that much and his stride should be more consistent. The remark about out of position is about fielding balls up the middle.
In my son's case you will notice he gets out over his landing foot thigh as he cranks down on the ball and releases out front
If there was a change in performance it usually occurred in the 5th but he often got stronger as the game went on.
The high elbow was one of the main things stressed with him. No one messed with his mechanics until late in his soph year at college. In an effort to get more velocity the coach made some devastating adjustments which were not good for him. I changed him back after his JR year once I saw what he was doing. He had his elbow below the shoulder and was experiencing a pinch feeling in his shoulder for the 1st time. Once he changed back he felt better and was getting late movement on his pitches plus got his velo back up to were it was. He had lost 2-3 mph. The change had also affected his pick off move.
Did you look at the other 2 videos ? The one shows him so you can see the ball movement.