Possibly its a mixture of all those things but possibly its also the fact that his footballing brain & ability isn't that good.
We certainly win more tackles in his area of the pitch with him there as opposed to Arteta or Flamini but it's what happens after that concerns me. Sunday also proved that his brain doesn't allow sensible mode when he's on a yellow card. Do we have to sub him now every time he gets a yellow ( which is virtually every game) because he doesn't have the sense to reel it in a bit.