I think something that has worked in his favour is that he failed in his first few cracks at test cricket. He seems to be a pretty odd, obsessive kind of character, and having failed early on went to work relentlessly on his game to try and eliminate weaknesses - as opposed to other more relaxed types, who might be more content to just shrug off a few failures and hope it's their day next time around.
That said, I am finding the plaudits a bit excessive. He looks a decent player, but he's had 6 months of good cricket ffs, and for 3 of those he hadn't even scored a century while the other 3 have been against notoriously poor tourists. At the moment he's simply a guy in very good form, and there's a long, long list of players who have had a golden season before fading away - especially those without strong first class records behind them. Like I posted in the tour thread, with the way his bat swing goes towards mid on, and the outside-to-in-to-out again way he drives at wide ones, he's going to have series where he struggles. Has had a healthy dollop of luck this series where the mistakes he's made just haven't cost him his wicket.