Interesting times at McLaren. When Jenson Button briefly engaged Lewis Hamilton in battle for the lead in Turkey, it was electrifying and, although the fight was subsequently called off and all appeared serene in Canada two weeks later, it may yet have repercussions.
Certainly Hamilton was surprised, to say the least, to see the other McLaren alongside in the Istanbul race's late stages. He clearly believed that, with the Red Bulls beaten and he having been the leading McLaren driver all day (and the man whose pressure had induced the Red Bull calamity), it was a done deal that he would lead the team one-two. It was a reasonable assumption.
But so was Button's. For half the race the team had been radioing him about fuel consumption and he'd heeded the warnings, repeatedly backing off from the lead trio for a few easy laps, then cruising back up to them again. His pace was every bit a match for theirs, he'd looked after everything, the Red Bulls were now out of the way - and Lewis was suddenly going slower. Why not pass him?
Why should he have his own race dictated by how much or how little fuel his team-mate had consumed? Jenson had fuel enough to get to the end, he'd bided his time. It wasn't his problem if Lewis had used more.
The team was not expecting this, had assumed its drivers would just hold position now. But that was how things used to be back in the days of two fuel stops: race up to the second stops, then hold position, wind down the engines, save fuel. With the single-tyre-stop format of today, there is no automatic defining point at which racing between team-mates ends. When Hamilton immediately retaliated and took his lead back, the team was quick to issue instructions to both drivers to back off and Button got the message, realised he wasn't going to be allowed to win this one.
There was initially some unease between them, Hamilton avoiding eye contact, Button jumping defensively into a Hamilton/Webber conversation that was actually about Vettel, but thinking it was about him. McLaren engineering director Paddy Lowe did some explaining to Hamilton before the podium ceremony, and then everything seemed to be okay.
But the incident will have underlined to Hamilton that Button is not part of his own championship campaign - and Button in turn will have been alerted to the fact that, in any future battles, saving the car needs to be played off against the need to be ahead of Hamilton sooner rather than later, when team tactics might come into play.
Essentially, to be sure of beating Hamilton, he needs to outqualify him - easier said than done.
The pattern forming so far is that Hamilton can get more quickly onto the car's pace at the beginning of a weekend, but that Button is better at improving the car through the weekend. But as he improves the car, so Hamilton tends to benefit too. On this form, if they were each in equally competitive cars but driving for rival teams, Button would probably be beating Hamilton. But because they're on the same side, it isn't happening quite like that. They've so far proved extremely equally matched and the differences are ones of degree, not magnitude, so subtle that the early-race positioning of one to the other is coming to assume crucial importance.
They were all smiles again by the time of the press conference and their personalities are such that you wouldn't reckon the team is on the brink of civil war - as it was in this stage of the Alonso/Hamilton pairing. But the terms of their fight have been made more explicit by what unfolded. These terms favour the characteristics of Hamilton more than Button, all-out attack more than fuel and tyre preservation. But that's only relative to each other.
Relative to the other teams, Button's style would probably be better more often. So there's a conflict there, one that is sure to become apparent again. It's going to be interesting to see how the team manages this and whether Button can evolve his approach.