Levy has to take the blame for the manger merry go round. Everything else he has done and said I agree with (based on the info we know). It has been his Achilles heel. Sacking HR and putting AVB in was backwards step. Levy hasn't been able to indentify and keep a top manager. He has done everything else. But for whatever reason, he's failed somewhat with managers.
Now, he needs a bit of luck and the right decision. I hope he goes for FDB. I think he is the right fit. What Levy had hoped AVB might be. No one has a crystal ball, but appointing key people is about making accurate judgements of character and ability. Then you have to support, giving confidence to, and identify the kind of help the new person may require to excell. My guess is Levy is hands off, but quick for the chop when things aren't working out. He needs to be more involved, understand and work closer with his man and make sure they excell. Its the one area we've missed.