Song did make a ton of stupid mistakes and is a very undisciplined holding midfielder. Wenger sold him for well over his real market value, after he led the team in assists last year. However, a like replacement wasn't signed to replace him. Wenger opted to rely on Diaby at first, huge gamble considering that it's Diaby after all. Now, Arteta plays deep and is very ineffective when pressured on the ball.
ETA: It was a good business deal by Wenger. But, as I told FOBUDan the other day, it was just stock trading not a wise squad decision.
This post was edited on 12/11 at 7:40 pm