ignore the scoffing of the upper division dolts
We "upper division dolts" actually have some experience on that matter, so if you don't want to listen, at least leave him the choice to listen to us or not!
When evaluating a trainee at the beginning of his career, ask yourself where do you want to be in three or four seasons. If your answer is "in higher league", go and see those higher leagues right now and check up some key players there. If your player can't match those key players because of his low potential, then don't bother with him. You will train him for two-three seasons and when you advance, you will discover you invested three seasons in a bench player.
At least this is my experience...I invested four seasons in two players with allstar potential and if I'd train them 1-position this season, they would cap, but wouldn't be good enough to be starters in my league. So what's the point in training someone you won't need at the end of his training career?