Question

Young player who has skills to be a marginal ML player. Will he benefit more from ML coaches or moving up the minor leagues.

I tried an experiment once....... A player I drafted I started him out at AAA and left him there for 3 additional seasons after his draft season. HIs ratings developed at the same speed as players I would start out at Low A and move up one level each season. That is a small sample size to base anything off of though.....

Playing time, coaches, makeup rating, and training budget all play a part in player development.

The word "marginal" is important... you have to be able to play him as much in the majors as you would in the minors in order to get the same development. If you can play him every day in the majors I think it wouldn't be a problem to do so... remember that you're using up pre-arb seasons when you do that, though.