Wade Miley is a work horse. With average to below average “stuff” Miley continues to get outs and get through tough lineups time after time.
I had the privilege of watching him in college. The “book” on him then was that he had threw across his body and had a slight hitch in his delivery before he landed. At times he could be erratic and lose focus. There was never a doubt about his competitive drive or willingness to win.
As Wade developed in the minor leagues he realized that he needed to step up physically if he wanted to have a long career. He rededicated himself to workouts and it showed when he was the Diamondbacks minor league pitcher of the year.
I believe the Diamondbacks tried to fix his delivery by taking away the “hitch” in his delivery and throwing across his body. I don’t believe they ever successfully fixed his stride because he still has that with the Red Sox. By eliminating the hitch in his delivery right before his stride delayed his arm action and now he doesn’t get his arm up like he should when he gets in the power position. You can see in the pictures below that his stride foot has landed and his arm isn’t ready to deliver the baseball.
In college he used to pick the ball up with his hand; now he does with his elbow which causes his arm to be late getting to the ready position. If he continues putting up 200+ inning seasons I hope he corrects this issue so he can maintain the durability he has had throughout his career.