What I was trying, imperfectly, to get at here is that Sam has the ability to command, to lead, that is intrinsic to him, and although he is not going down the path of becoming Lucifer's Boy King, there is still that power, that quality to him that was partly why he was Azazel's favorite to take on that role. So here, I meant to show that Sam still has the Command Voice, and more importantly, to show Dean, just once, seeing the Boy King in the boy, seeing that commanding aspect, really registering that Sam was being groomed to be someone of immense power, and being motivated by it to be lovingly submissive. Otherwise, with Sam being his younger brother, that dynamic would be hard to achieve in a plausible fashion.

Sam is special, and has developed certain skills and powers. He still has those, even though he is no longer going to be groomed for evil. So I'm exploring that. I don't even know for sure where I'm going with it, but it's working for me so far. :)