One thing to think about- Molina had the puppet arms to interact with only in some scenes. In others, he had to imagine the arms and anticipate how they would move about his body once they were CG'd into the scene. That had to have been interesting. I'm sure that he knew that the CG would be affected by every move he made; so he may have been "conducting" in a sense, almost speaking to the CG animators with his body and making suggestions to them...