"So will the new chief make a difference? Not unless he can change the behaviour of Donald Trump himself…"

And there is the reason that Kelly will fail to bring order to the dysfunctional circus as surely as day follows night. Trump is so full of himself and has such a colossally  misplaced belief in his own infallibility that he is pathologically unable to listen to others. 

The sooner it all crashes down for Trump the better for America and the world.