Yeah it is really isn't it, because Fellaini and Gibson essentially start doing similar jobs. You could say Gibson has taken Arteta's role (and doing it better than he did in his last 12 months which pains me to say), and I remember a lot of 5 yard sideways passes and generally not getting very advanced on the field. At least Felliani is an outlet.
A Fellaini Gibson partnership looks good on paper because Fellaini can charge about being destructive and winning balls and Gibson can watch the runners and mop up if Fellaini doesn't win it and present for the ball and then pick the long passes from the back if Fellaini does.
In practice, we haven't really tried if often enough to judge.
Fellaini's great asset, no matter where he plays is his ability to win balls, aerial balls, challenges, whatever. He's great at getting the ball, shrugging off challenges and passing it on. The main reason I prefer him further up the pitch is that the higher he wins it the more attacking it is for us and also the less drastic the consequences for him going for a challenge and getting beat by runners, which happens to him as a direct consequence of his style and that he looks for the ball more than he looks to hold a position.
Playing him behind Gibson would I think cripple both of them, Gibson wouldn't get the time on the ball he currently enjoys and Fellaini wouldn't get to charge around trying to win the ball and bring down hoofs. But in front of Gibson, with four runners beyond to aim at, it could turn out to be brilliant. We haven't really tried it.
I just really like the way we currently play, to be honest. I don't want Moyes to change what might be the first of his teams I unambiguously love.