The one thing I'd worry about is if he loses what he has by trying to learn a new pitch. Sometimes when you do this (learn a new pitch), you lose your arm slot or mechanics in the things you have been using. Yeah, I know...what he has know isn't working but imo it's a hard thing for a guy this age to do and change (pun intended) is hard. he seems like a hard worker, he might be open to learning a new pitch at this stage, if he wants to remain in the bigs.