You can see the hips are toward the plate and the shoulders are almost 90 degrees facing the base (1st or 3rd).
Chapmans is 6'5" and still gets deep and long into the front leg, but if you look at Oswalt and Licecum they are 5' 11" and 5'9" and their front leg is farther and deeper than the others.
To get an idea of the shoulder separation and what is happening in the core, look at the jersey stretching near the belt and follow the lines up toward the throwing arm, and imagine that stretching as core muscles.
Pitching is all about the engine (legs), transmission (core), and braking system (back and hamstrings). Pitchers create load with the back leg, unload the back leg with explosive foot turn over into triple extension creating quick hip rotation, front leg is a deep lunge at foot strike, shoulder separation occurs because of core strength, and a clean table top finish requires the front leg to go from a deep lunge to a straight leg using the hamstring for stability. If you are not using your engine, transmission, and braking system you are generating and absorbing energy in the arm, elbow and shoulder, which leads to arm problems. There is a saying in pitching "The arm just comes along for the ride."
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