"I wouldn't say it's an easy job, it can only get worse I suppose!" said Pietersen, after completing another incredible chapter in the tale of his accession and acceptance into the top job of English cricket. "I've been getting a few text messages asking: 'Who writes my scripts?' but I don't like to make mountains out of molehills. I just like to be as simple as I can, and I'm just playing the game that I love."
Regardless of its magnificence, the most incredible aspect of Pietersen's first two days in charge has not been his century - let's face it, it was as close to inevitable as a sporting feat can be. Rather, it is the extent to which his team-mates have bought into the cult of KP. Those who doubted the appointment never questioned Pietersen's ability to score runs, they merely feared his inflated ego would squeeze all other incumbents out of the dressing-room.
And yet, there was Steve Harmison, grinning ear from ear as he compiled his highest Test score, and alongside him was James Anderson - another player who had been prone to introspection in the former regime - unfurling reverse-sweeps during a helter-skelter tail-end stand, before curling a peerless inswinger into the front pad of Graeme Smith, as he took the first over with the new ball at the close of a manic day.
Those were not the performances of men who feel marginalised by their new lord and master. "I've been getting to know more about the players and how they operate, and that's come on in leaps and bounds in the three or four days I've been in charge," said Pietersen. "It's given me a really different perspective, and now when they are batting I really want them to do well for me and for the team. It's more of a holistic type of thing, which is great."
It is too soon to pass judgment, but the feeling grows with every session. There's a spark about this set of players that was not visible even when England were turning their early-year fortunes around against New Zealand. Back then, everything relied on individual feats of brilliance - in particular, game-changing five-fors for Anderson at Wellington and Trent Bridge, Ryan Sidebottom at Napier, and Monty Panesar at Old Trafford.
Now, despite the assumptions that he'd prove to be a selfish leader, the collective is what really seems to matter to the new captain. "More than me getting a hundred, I really wanted Steve to get a fifty today, and an even bigger score," said Pietersen. "He's deserved it. After being away from the game for six months, to see him back and smiling and laughing, the cynical little man that he is, it's great. It's lovely to see him back."
Such gushing is the new leader's way, although it was noticeable that, on the subject of his own innings, Pietersen was diplomatically succinct. This wasn't destiny, he insisted, merely "another day of doing the simple things as best I can, and doing them right." He described a handful of loose strokes as "funky", but reiterated that, for the most part, he played straight, and in his areas. It was true as well, but you wouldn't normally expect such a modest self-appraisal of another remarkable performance. There is no "I" in team, as the old saying goes. Perhaps, henceforth, there will be no "I" in Petersen either. Or at least, significantly fewer.
But if the way in which he is talking about his performances has altered, there's no immediate danger of Pietersen carrying the burden of responsibility out into the middle with him. "You can't be a captain when you're batting," he said. "You just have to go and bat, and make sure you try and score as many as you can. All the nonsense that happened before the game, the scrutiny and the attention, you've got to get on with it, but I was so happy when I flipped the coin yesterday and knew the cricket was on the way."
There was, if you were on the look-out for it, the vaguest hint of "I told you so" in Pietersen's voice, as he metaphorically screwed up the acres of newscopy that have poured forth this week and lobbed them gently but firmly back at the assembled journalists. But for the moment, he knows that he is untouchable, and is content to sit back and let the occasion do the revelling for him
"You have to do the press conferences and live the life, but the cricket is what I love," he said. "Before the game I still did the right things and the right amount of work that I normally do. I just have to give that extra time and responsibility to the other players, to build their confidence and speak to them, which I don't mind, it just keeps me involved a little longer at training.
"If I am having a good day today, or yesterday was a good day, then it was a good day," he said. "I've had lots of bad days, but I've had a lot more good days than bad days so far in my career, so I'll just keep doing what I normally do. But it's probably no surprise that I keep improving, because I wake up every single morning trying to get better."
Andrew Miller is UK editor of Cricinfo