I think a lot of it has to do with recruiting. If he feels he's behind for some of our targets and needs to be pounding the pavement, then I think he may stick to Sampson, Gathers, and Obekpa like glue for the rest of the season. Plus, I don't doubt that his condition makes him more suited to engage in that type of work. And if he thinks it's in the best interest of the team to use his limited energy like that; I'm not going to second guess him.
Second, I STRONGLY disagree with your implication that the players don't respond to Dunlap's teaching methods. J Branch did nothing but rave about the coaching staff and the teaching they did in practice. Initially, the freshmen may have bucked a little. But that's natural, we all know they were big talents who were coming from very unstructured basketball. I think by this point in the season they've seen that you win by doing the little things they are learning: setting picks, moving without the ball, spacing on D, etc etc.
I don't know where this notion came from that the players were "fooled" into thinking Dunlap wouldn't play a big part in their basketball future. Sure, they signed up to play for Lavs, but anyone around the program saw that he trusts Dunlap with quite a bit of responsibility. It wasn't uncommon last year to see coach Lav turn the huddle over to Dunlap during timeouts. And these recruits were sitting behind the bench, so they clearly saw that as well.