I don't think we're understanding what Fisher's idea of team psychology is. Since we don't know what he's trying to do, it's hard to evaluate it.
At the minimum (based on books by Phil Jackson), I think he's still figuring out what's he got on the team in terms of "intelligence, mindfulness, compassion, joy, competitiveness" . . . and what he can do with it.
For example, unless Williams is injured (that we don't know about), you'd think he should be playing more minutes. But he's not. Must be something that Fisher sees (in terms of overall plan) that we don't.