This is the way I trained when I started this game. I always did Team training, but I bounced around from skill to skill. Not just Jump Shot. What ends up happening is that after 2-3 seasons you end up with a roster full of 10k guys that aren't really good enough to start, and nobody really wants. I'd suggest finding 2 to 3 really young trainees with at least all star potential and focus on single position training. That way...these players will eventually be good enough to start for you, or you can sell them for big money. Good luck.