It was always going to happen. Given how closely matched Nico Rosberg and Lewis Hamilton are up front, it was only a matter of time before there was a repeat of the Spa 2014 collision that cost Mercedes a victory. And it finally did happen in last Sunday's Spanish Grand Prix.
I agree with Niki Lauda that Hamilton was at fault. There have been a few occasions where the world champion has been a bit brutal with Rosberg, who on this occasion held his own.
But what both drivers need to remember is that the throttle works both ways - you push it down to go faster and you release it to go slower.