"Here is Koufax in a "real" film."
There's no question that Koufax's timing is different in this clip, although I would disagree that his shoulders are 95% turned at foot plant. By my estimate, Koufax's shoulder rotation is nearly 180 degrees, and at foot plant his shoulders are turned maybe 75 degrees.
I think part of the difference may be due to the difference in the pitch. In my frame, Koufax has a fastball grip. In your clip, he is throwing a curveball (which hits the outside corner for a strike).