I meant conceptually because of what you say in your edit. As far as your state variable is concerned, they are parallel. But as you point out, there is implici

I meant conceptually because of what you say in your edit. As far as your state variable is concerned, they are parallel. But as you point out, there is implicit screen state (either in the code or in the GPU or wherever) and when updating that, order certainly does matter. If each draw* function drew to a temp buffer to be composited later, then they could be parallel. But none of this is really relevant to the game-state discussion, though, since we were both talking about (and agreeing, I think) that decoupling is good regardless. Even if just to aid reasoning.