Yeah, after training bigs and guards, I'm now attempting to train SF, because like you said, they are very high in demand. While training SFs is a pain, I think I've come up with a good system. Now, yet again, I am blowing up my team.
By the way new owners, don't play Princeton and DO NOT buy players you think will fit Princeton well. I'm cutting my losses and moving on from this bad idea.
I agree, if you're training guards, then buy quality vets for your frontcourt. A new player should not try to train SFs. Training is very complex and I learn something new everyday.