>>> Justin looks like a fine hitter.
Look closely. He does not have the lead elbow, lead arm and barrel lined up in the swing plane so as to allow shoulder rotation to power the swing.
Swing a bat and try to duplicate what you see. Video it. You won't duplicate what he does by doing the above.
The hands do something that causes the lead elbow and arms do something completely different.
You can prove it to yourself if you'll do the above.
Justin's barrel rotation is centered in his hands.....not his spine. <<<
You are correct, Justin’s bat-head is rotating (or arcing) about his hands. However, as we can see in the overhead clip of Rose below, his hips, shoulders, elbows, and hands do arc about his spine. Then on the outside of those arcs, is “The Final Arc,” the bat-head arcing about the hands. The swing mechanics that generate maximum rotation of the bat-head around the hands is what our Instructional DVD “The Final Arc II” is all about.
Overhead view of Pete Rose