I must have missed that from Ornstein. Joe Cole recommending Chelsea over Arsenal is hardly surprising though. I won't be surprised if Wenger had lost appetite in the end of such a long stint at one club, he was no Fergusson. I felt that was a reason he needed to go too but I just don't see that as him being comfortable and leaving such an ingrained culture either, which will loom large even after he was gone. If that was the case then Louis Van Gaal and David Moyes would have fared better at United because of the culture there. It's as if player quality counts for nothing. Wenger and Arsenal recruited players who weren't good enough, and hence failed, not because he was comfortable with failure. Emery is in part struggling because he doesn't have the best players although everyone felt any manager could come and get the existing players to perform better than Wenger was.
Chelsea have won 5 titles since the time we last won the title but they have also finished outside the CL places thrice. Joe Cole can talk about culture because their owner has done whatever it took to build successful teams, not because their managers didn't accept less. All starts from the top and percolates down.