I think often times there are situations where a team gets big break out years from players propelling a team to success. A good GM will know if a guy is coming into his own because they are tracking his development closely. You might want to argue that you can predict break out seasons from stats on paper. I would disagree with that. Most of the break out years predicted by experts are busts. A good GM knows his players. The reports from his coaches are better indicators than numbers. You can't put together a team of .220 pop gun hitters with pitchers with 5 ERAs and expect to compete, but building a team is not about assembling numbers except in Fantasy leagues (which I excel at BTW). If you build a good team, they usually come along with good numbers. If you are emphasizing building a team from stat sheets, I would disagree with that emphasis. Look at Carl Crawford-- great numbers, but he clearly didn't like or want to play in Boston. That is something that should have been unearthed.