Just a fortnight ago Whitmarsh suggested in the wake of the Indian Grand Prix that one of the reasons behind Hamilton's rollercoaster season was due to the pressure he was under from team-mate Jenson Button.
It was a remark Hamilton derided last week as "rubbish", instead insisting personal issues had mentally affected him, resulting in his run of incidents and penalties.
On Sunday, Hamilton returned to form with a superb drive to win the Abu Dhabi Grand Prix, his third victory of the season to match that of Button.
With the curtain due to come down on the season in Brazil in two weeks, it prompted Whitmarsh to cite the likelihood of a battle between his drivers for a defining fourth win.
"I'm sure both of them think they can make it four by the end of the season," said Whitmarsh.
"I know them both well enough that they will want to be the driver who comes out of the year with four wins. They'll both fancy their chances of winning in Brazil."
However, it was an observation that surprised Hamilton as he said: "For the life of me I don't know why he would say that because that's not the case.
"Of course we both want to win, but it doesn't matter whether he or I get it, we still end up on a high. That's my view anyway."
At least Button is up for the challenge, particularly following his issues at the Yas Marina Circuit.
A faulty KERS power-boost system denied Button the opportunity of battling with Hamilton after Sebastian Vettel had retired at the end of the first lap with suspension damage following a puncture at the second corner that spun him off track.
"I'd love to fight for the win there," said Button, looking ahead to the season-ending race at Interlagos.
"Obviously Lewis will feel the same, and we'll have a good scrap hopefully, although I don't think we'll be the only people in that scrap.
"Seb is going to want to come back strong, Fernando (Alonso) is on top form, the Ferrari is working well.
"Felipe (Massa) has something to prove at his home grand prix, and Mark (Webber) wants to do a good job and have a clean weekend.
"So there will be six of us really fighting it out that weekend, so I'm excited about the challenge, and it would be lovely to get the last win of the season."