Another thing heavily in his favor is the very clear rapport he develops with the players, especially the younger ones. His age helps on that, because he's just old enough to be seen as an authority figure but still young enough that they would have grown up actually watching him play. So he gets a tremendous amount of respect from them for that.
And that translates into them listening to his coaching and actually getting better. I mean, what he's done with Iwobi is downright miraculous - from a player most couldn't wait to be rid of to one of the first names on the team sheet. We're seeing Gordon and Patterson showing fairly quick improvement too, and "marginal" players like Davies and Holgate have also been improved enough to be pretty dependable contributors so far this season.
Give the man enough time and another solid window or two of backing in the market, and I think we'll have something really special going on here.