UKD keeps dragging us down a path of pedantic technical comparison with ballroom.
I don't, you know. I only usually mention BR in response to someone else's comment. I'm sorry you find my writing pedantic. Perhaps I'm a pedant.
It is odd that UKD is insisting that ballroom doesn't use the arms, when in comparison to tango it has a much more rigid arm frame, and yet when he comes to tango, which is usually taught without an arm frame and is lead from the centre, he is insisting he uses his arms. From his writing he should be an expert in leading from the body whereas coming from ballroom I found I had much to learn for successful tango.
I never claimed to be an expert in anything, but I don't 'use' the arms consciously. They are just antenae, and at present, I find that less is more.