If you're training 3 positions you can split your player's minutes. He could play 16 mins at PG, 16 at SG and 16 at SF, for instance. The big argument above was because you didn't mention that you had another SF in line :P. I'm also training an SF in OD, but since I need to improve my two PG's OD quickly (their defense is killing me) I'm playing the SF as an SG in scrimmages so train 2 positions instead of 3