I don't think his improvment would have anything to do with the coaching staff. Here's a recipe Trent's improvement:
1. 1000 jump-shots/day from aroun10-15 ft. With his quickness, if he can force a big defender to play away from the basket, Trent will eat his lunch. As for now he can't do this.
2. 100 free throws/day. Let's face it, if he can't hit a free throw, especially because of how much he gets fouled, games will turn into a hack-a-Trent.
3. 500 jump hooks from the low block (primarily going to his right hand). While he has improved with his right hand, it is no where near where it needs to be. Just watch the games against teams with smart defenders gaurding him...they all forced him to the weak hand where he often threw up his flailing wild hook shots that almost never went in.
4. Foot work practice. His drop step on the right block is good, but he needs to focus on his drop step from the left block to the right hand
None of this requires a coach to be present, just hard work and dedication.