You are rewarding bad managers that didn't look at agresiveness when they bought their trainees.
This sentence doesn't make any sense, sorry mate.
There's no way to know how aggressive a rookie is. And bright prospects are, in my opinion, always worth more right after the draft than when they're 20-21-22 yo.
So you're basically saying that managers who buy aggressive rookies are stupid whatever they do, because training an aggressive player is stupid, and selling a player for less than his purchase price is stupid - or at least is a "long-term strategy mistake" (unless he's old, of course).