It looked like his hand was supinated in his fastballs to me. Ill have to look at it again, considering you probably have a much better eye than I.
The medical study saying that the forearm was supinated in the FB, just not as much, would definitely be a batter reading. It said This:
"The motion of supination/pronation of the forearm and dorsiflexion/palmar flexion of the wrist prior to the ball release; the forearm was supinated more in the CB (maximum supination: 39.9 &plsmn;6.0° at 0.072 &plsmn;0.045 s before ball release, or BRL) compared to the FB (19.4 &plsmn;8.5° at 0.076 &plsmn;0.046 s before BRL)"
unless the readings they gave for the forearm mean neutral, because the arm is already supinated to lay back?
(Even though it's pretty much entirely what I'm unintentionally doing) - I don't mean to try to "prove you wrong" - just trying to elicit discussion on this.