That's the obvious answer, but... I don't know, in terms of balance, it would completely change the complexion of the team. I can't see Bale or Son putting in the kind of effort Lucas does and a lot of managers, Mourinho even more so, love hard-working forwards. Plus, not so long ago, he gave an interview in which he said that Lucas' problem was that he never had a coach willing to play him week in, week out and that intended to give him a lot of playing time... Maybe he'll rotate the three of them depending on the profile of the opposition full-backs but I'd be really surprised if Lucas found himself in Davies' situation.
Ha, what was I thinking? Mind you, I think Mourinho enjoys these headlines. He seems to enjoy that 'siege meteorology' that served Ferguson well at Manchester United. He likes to have a small-ish group of players who buy into his philosophy and are willing to go to war for him. That's probably the reason why I complained about having 'too many players'. It's difficult to be seen as a cult leader by a guy who hardly ever plays for you.
Bale will play "big games", we need to manage him, I'd be delighted if we got 30 games out of him, plenty others for Lucas, also we could give Son the occasional rest, play Lucas with Bale on left.