Ok, here's the update. I pushed. He was sitting on the bench behind a player who did not appear to be more talented. I asked him if he was going to let this [blah blah blah blah] beat him out of his job. I said you need to play big, play with confidence, out hustle, etc. A full blown speech.
Long story short - and I am shocked to say this - he changed his ways. He "manned" up and took the job back. Started on varsity the last part of the season as a sophomore, plus the post-season.
It was an incredible transformation. I have never been more proud. Let's hope it continues.
My NEW advice - trust your instincts. What works for one kid might not work for another. What works one year might not work the next.
Just like everything else in parenting!