Originally Posted by SCCWS
The media will tell us that Don Cooper is a highly rated pitching coach. But I struggle to list what pitchers have developed under Cooper to the point where they are considered top major league pitchers. I do think Cooper gets some credit for Buehrle's development even though he had a great year before Cooper became the pitching coach. But certainly Jenks, Floyd and Thornton are not top pitchers. I can't think of any pitchers that Coop developed that was traded or signed elsewhere. Gio obviously developed after he left. There must be some top pitcher that came up and developed under Coop but I can't think of one
You can not just magically turn average to slightly above average talent into a top tier pitcher. He generally gets more productivity out of pitching talent than most pitching coaches.
Jenks was a top tier closer for a few years before his arm and body could no longer withstand throwing 100mph with a power curveball (among other things).