Not sure mourinho will success in the first year with manchester united, seems it will be hard for all manager to win premier league this year since many good manager come to premier league to fight each other to be the best.
Its difficult for any manager to success on first year, sometimes we ask more than they could do. There are other big managers and good players on premier league. They need good luck to win, what we can ask managers and players is playing at its highest level, nothing more. If they play at its best and don't win, its because they haven't luck.