I am completely and utterly flabbergasted that Manchester United confidently believe that bringing in a manager who has some (but not a great deal of) pedigree is going to turn their fortunes around almost instantly.
I don't think they're going to get a great deal of the "new manager bounce".
I sincerely think he could be gone before he even gets his feet under the table - two/three months? They will not tolerate failure, though in fairness to them they should be used to it by now.
My prediction: He will not be there at the start of next season.