I didn't know him as a 12yo but he's a example of a stud who kept working on his game and got drafted very high, still has a long way to the majors but he's off to a good start.
The point is that the initial poster made the comment that he feels EVERY mlb player was a stud at 12 and THAT's why he go some of the responses that he did.

I would guess that most mlb players showed signs of greatness at 12 but I doubt that all were studs that dominated at a high level.