Steve A., I respect that you said you’re done, but let me throw this out there: I don’t think this is an issue of PCs “commanding” pitchers to change their deliveries. Just looking at MLB relievers, it is clear that most do not use a windup, even with bases empty. There is also no trend I can identify of relievers who are aging and losing velo switching to a windup to gain speed. Maybe Mariano Rivera never needed the extra mph from a wind; but what about all the marginal guys? To agree with you, don’t I have to conclude that the guys who are the best in the world at what they do, and who have access to the best coaches, don’t act on what seems obvious to you? No disrespect intended (and I am no pitching expert), but I can’t reconcile what I see in real life with your explanation.
Nolan Ryan might be one of the best examples that what works for some won’t necessarily work for all. The guy’s skill and longevity were incredible. But even a really gifted P who copies Ryan’s delivery may not throw as hard as that P could using a different motion, and may end up injured. The more I read and study, the more mysterious pitching gets. I’m reaching a point where I’m afraid to teach pitching to the 9-year-olds I coach, because I’m convinced I don’t know anything.