"I would say that the distinction isn't relevant to the issue of "accounting" for the mind as a physical phenomenon."Logically if any view ( physicalism or some other model ) can account for all views, then it is hypothetically possible that there could be only one such view in the set, and that it could be your view, in which case, it would account for your view. This means that the number of views that are accounted for isn't relevant to the issue. One or many. It makes no difference.
I would say that the distinction isn't relevant to the issue of "accounting" for the mind as a physical phenomenon. I would only agree that the external world is separated from one's subjective experience, and therefore they cannot be one in the same from a contextual perspective. However those who are of the view that the only things that exist are subjective experiences would argue otherwise.
Well, yes... if you want to account for mind as a physical phenomenon the distinction isn't relevant. A physicalist doesn't think there is anything additional to account for! That is exactly why physicalism isn't sufficient, since, if on my death bed I were fortunate enough to have that physcial explanation laid out before me in all its splendour, I'd still be pretty pead off that I had no idea why I existed and was about to cease to exist.