I imagine it's something along the lines of "ok device, you have 10ms to play with the link before anyone's watching, do what you need to do." For example, ele

I imagine it's something along the lines of "ok device, you have 10ms to play with the link before anyone's watching, do what you need to do." For example, electrically detecting the wattage of the power supplied over the link by examining its responses to various inputs. (I have no idea whether that's at all relevant here or if it's even the right part of the stack, I'm just offering an idea of why the device might like the controller to say "I'm not watching right now".)