I think it's people are fooling themselves if they dismiss Diaby as a footballer based on what we've seen of him so far. Yes, he has had some abominable performances for Arsenal, but he has also had some outstanding ones. His whole career here has been a struggle with injuries and the way I see it - most or maybe all of his weaknesses were (yes, I'm using past tense with him now, might as well) the kind of problems that would have improved with experience:
- Bad positioning
- Running into dead ends
- Bad decision making
- Struggling to define his role on the pitch in every match
I think Diaby was also a bad fit for the static tiki-taka football we often played in recent years. That majestic performance against Liverpool most likely happened because it was a more open game, as Liverpool games usually are. This season, when we have started playing faster, more direct and with more pace, I think Diaby would have been brilliant for us.
Seeing him at his best a few times was enough to deduct that there was an amazing footballer in there. That he couldn't bring it in every game has many explanations, but in the end it all boiled down to him never getting the chance to work hard at improving himself as a footballer, because he would be in the treatment room more often than not.
But whatever, it's all academic at this point.