I just reread my post and realized that I left out an important part! When Duncan tried to lie down, Eric did not LET him because Duncan was making the decision to lie down, not Eric and Eric was the boss! Duncan was just trying to get out of doing what he had been told by trying an alternate to standing up and since he was told to SIT, he needed to remain sitting. Carrie, this goes back to the decision making that Duncan was doing. iI says a lot for his intelligence that he tries one thing and rather than keep trying it and failing, he tries other things. But again, he was making a decision rather than following his leader.
So that said, maybe that whole thing makes sense now from a training perspective!!