The most poorly coached pitching mechanic of the high-velocity pitcher is the Load Position which is the position when the pitcher has prepared the drive leg for the drive. Not teaching a pitcher to put the drive leg into a linear position with flexion would be like...
Sometimes things happen for a reason. I remember this average looking pitcher walking into my camp about 6 weeks ago and watching him throw a short pen as we recorded his velocity. I will never forget seeing that first pitch. It wasn't that impressive but what I saw...