My sense of the issue with Miller (based mainly on some of his own offhand comments in interviews and Brad Richardson's recent remarks) is that he's driven to distraction by the performance of his teammates. He feels an overriding need to tell them what they should be doing better and it's not something that he can just turn off. Let's set aside the notion that he's an imperfect messenger for telling everyone else what they need to do. Let's say for sake of argument that he performs like Sidney Crosby on the ice. Even if that were the case, I can tell you from personal experience that that kind of behavior wears thin quickly. Perhaps it's tolerated more in a professional sports team environment - probably it is because winning trumps everything else. But from just a baseline human-to-human kind of level, no one likes a busy body. It's grating to be around.
So yeah, maybe in that one instance, it was unfair to Miller the way that Tocchet benched him. But if it was in the context of him yet again asserting himself as the self-appointed mayor of everything, I can kind of see it from Tocchet's perspective as well.