My main objection with Nasri in that AM role is that I don´t think he is that good at spotting his team mates´ runs. Playing in the middle I think he holds on to the ball way too much.
IMO we need BOTH Nasri and Arshavin, along with one from CM to make plenty of runs behind the back 4. I have no doubt that either of Wilshere, Ramsey or Rosicky have the ability to play those balls if there is enough movement in the front of them. Off the top of my head the much slated Rosicky has put Arshavin through at least three times this season. He STILL has that ability.
In the game at Old Toilet we could have had Maradona and Xavi in our midfield and they wouldn´t have been able to find our front 3. They were standing absolutely still, just wanting the ball played to feet. We can´t have that.