It's fascinating how healthy teams find the right balance in unpredictable ways. The principal thing is that they be allowed to do it. Managers who operate on the assumption that they're supposed to decide matters so often intervene to wreck them. It seems strange, but it's simple cognitive dissonance. It's psychologically difficult for middle managers who add no value not to interfere, because that would mean admitting that they add no value. So in order to prove they deserve their authority, they interfere and cause harm. That's not true of everybody in such positions, of course. The smarter ones understand that mostly what they need to do is nothing, just let people work - sort of like the new-age Buddhist saying, "Don't just do something, stand there!" But it's true enough in bulk that that whole organizational form is irrational. It is gradually being replaced.

In any case, you've provided a nice example of how issues like working hours are subsumed by team dynamics. That's where action is.