Whoever it is should sort their own shit out before telling Wenger what to do. What the fuck would focusing on the opposition do? Giving the ball away on the half way line isn't an opposition specific issue, Vermaelen letting the ball run in the area and then not being alert for the rebound isn't an opposition specific problem, Lukaku scoring from the wing after pathetic attempts at defending from Nacho and Verm again is not an opposition specific issue. Same with all the other games, say what you like about tactics but every single one of those games has been riddled by pathetic individual errors. It's like we've got 11 Clichy's out there who could do something stupid at any moment.
Wenger needs to smash these guys around the head and get them to focus on what they need to do, instead it looks like he's trying to protect them. His mentality is all wrong and it's transferring over to the players. They look like they're fucking sleep walking half the time, how they perform almost depends on how the game is going.