Good question,
IMHO - It is a learning process from the time the pitcher decides he wants to pitch which may begin in little league. He learns something new every year and builds upon his arsenal at every level. When he hits his senior year in high school, you hope the "projectability" is there for the college or MLB scouts. I wouldn't think too many Cy Youngs come out of high school. The degree of "projectability" that a pitcher has can be seen by the amount of the signing bonus for MLB and for college I would think it would be the stature of the college that awards the scholarship. As to whom develops a pitcher better would be difficult to asess and probably will vary from college to college and MLB org to MLB org with good and bad in both.
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