A number of factors at play here I believe Willie.
Nr.1 Certain quarters (journalistic far more so than irrelevant web jockeys) not giving Casey the respect due for an utterly dominate title in 2007 on a very difficult motorcycle.
Nr.2 Pressure to perform and repeat that title on a still difficult and virtually undeveloped motorcycle in 2009/2010. Mainly pressure within himself and frustration with Ducati Corse.
Nr.3 Complete vindication from all quarters (except a few web loonies) of his difficult Ducati years by the abject failure of the dominate rider of the past decade to get to grips with the GP16. Together with some very well deserved Schadenfreude on Casey's part.
Nr.4 A machine (RCV212) in which he has confidence and he doesn't need to take to the very edge constantly to compete. Christ that must have been a difficult thing to do week in week out on the GP16 and incredibly mentally taxing and draining. He can now ride within himself and only push when he really feels the need / desire. Any other time he can have that 1-2% buffer in his back pocket a take a mere podium. And he's still peaking. Isn't a racer supposed to be in his prime at around age 32?
Nr.5 Real respect between Stoner, Lorenzo and Pedrosa.
Nr.6 Good old fashioned maturity. An apparently happy and stable domestic situation with a kid on the way. How many of the slandering dickheads on here had any maturity whatsoever at age 25 (of course half of them are still only half this age now, the other half remain half the mental age) let alone at age 21 with a world title in his sky rocket.
Put all the above together and you see a relaxed and confident Stoner willing and able to fully express himself on the motorcycle and show us just how damn good he really is. He's in a really good place in life right now. Good for him.