i listened to some pitcher guy on the radio talking about shields. said that he is twisting too much when he pitches or something like that. which apparently makes his pitches move too straight, especially the changup. the royals should have him try twisting less the next time he has to pitch.
the pitcher guy said it was a common problem for shields. he has to always fight being overly twisty - that's when he goes in his bad stretches. i think it was a teammate from tampa or maybe a coach.