Like that quiet friend who turns into a wildly passionate animal after a few drinks down the pub on a Friday night, something must happen to Colin Kolles as soon as he walks into a team principals' meeting.
In public, Kolles is one of the most mild-mannered, calm and considerate of Formula One team bosses. Always happy to stop for a chat, never ducking a question, and perpetually having a cheeky glint in his eye that betrays him knowing something that you don't - but wanting you to probe to try and find out exactly what it is.
Yet speak to rival team principals about their gatherings and they have been left in no doubt about just how passionate, determined and aggressive Kolles can be when it comes to securing what is best for his F1 team. His fist banging has become something of a trademark in recent weeks as the customer car row escalates ahead of what may be a showdown at the Australian Grand Prix.