I don't agree that it was more Hamilton's fault than Button's. Jenson clearly knew Lewis was there after he was slow exiting the final chicane - his head tilts twice as he is watching Lewis hard in his mirrors. The incident is 50-50 blame in my view at best. Jenson said post-race that he had apologised to Lewis.
Button was partly at fault in his incident with Ferrari's Fernando Alonso.
Hamilton and Button collide in Canada
If you compare the collision between Button and Alonso with that between Paul di Resta and Nick Heidfeld, I'm not sure Button was any less to blame than Di Resta was - and the Scot got a penalty, even though he had a damaged front wing and therefore had already paid the price for the contact.
Alonso was ahead, Button was no more than halfway alongside and the Spaniard was entitled to turn in. He gave Button space, and the McLaren under-steered on the slippery kerbs into the Ferrari.
There were so many inquiries after that race that thankfully Jenson's spectacular victory was not taken away with penalties. This would have been very cruel on the fans who loyally stayed with the longest F1 race in history, although the stewards must be consistent.
Button said in the news conference that he thought he had pitted eight or nine times. It made me smile that the race was so complex and manic the winner thought he had pitted 50% more than he had.
It was the latest of several wins Button has taken in mixed conditions - starting with his maiden win for Honda in Hungary in 2006, through Malaysia 2009 with Brawn and his two victories for McLaren last year in Australia and China.
Button is very smooth, precise, and consistent with the car. That style comes into its own in those circumstances, allied to sheer confidence. He seems to attack more in those conditions than in the dry sometimes.
His pace in the closing stages forced Sebastian Vettel into a mistake on the last lap. I presume Vettel was worried about the DRS zone at the end of the last lap and he just got in too deep into the Turn Six/Seven chicane, although he did well not to spin his Red Bull completely and lose second place.
It's nice to see Vettel is human and can make mistakes - but he still finished second. And to be fair to him, he handled four safety car re-starts superbly and drove impeccably from pole until that final lap.
He was beaten, but - just like in China - only just. And Hamilton and Alonso did not score any points so it was actually quite a good day for Vettel.
He is annoyed with himself for doing that, and I have no doubt he will turn up in Valencia at the next race ever more determined.
'Special weekend' - Button
Wet-dry races are always good, and this one was no different, despite the painful two-hour red flag period.
My one regret is that Hamilton and Alonso were not in that mix as well. It was very exciting as it was - add those two in alongside Button, Vettel, Webber and Michael Schumacher and it would have been truly epic.
I know there are a lot of fans, particularly Michael Schumacher fans, who are saying it's fake racing, that their man was robbed of a podium because of people passing using the DRS overtaking aid.
There has always been a lot of overtaking in Canada and, on the face of it, it is the last track you would think needed two DRS zones.
But everything may not be what it seems. First of all, everyone has the same opportunity of having DRS available although the front of any pack is always exposed. But - just like in Turkey - the overtakes may or may not have been caused solely by the DRS.
There are differing wing levels and gear ratios to take into account, KERS, corner-exit speeds, and tyre wear which is higher on the Mercedes than some other cars. The Mercedes is not the fastest car either. All of those factors could have had an additional influence on the ease with which Schumacher was passed by Button and Webber.
It was by far the most convincing demonstration that Schumacher can still cut it since he returned at the beginning of last season after three years in retirement.
He wasn't clumsy in traffic, he made good moves on a day when others made mistakes, and he was very fair when he was being overtaken. If you erase your memory of the last year-and-a-half, it looked like vintage Michael Schumacher.
“I think F1 should push the boundaries out a bit more - the safety car should be a last resort, not a default option”
There was, of course, a controversy about the use of the safety car. There were two main issues - should the race have started under the safety car, and did it stay out too long at the re-start after the red flag period?
Most clear-cut is the re-start - the fact that the drivers came in almost immediately for intermediate tyres tells me that, on the face of it, the safety car was out too long, although it may emerge that there were good reasons for that to be the case.
As for the start under the safety car, you have to walk a mile in race director Charlie Whiting's shoes.
He has drivers saying they can't see where they're going, it's too dangerous, the track's waterlogged. If he starts the race in those circumstances and somebody gets hurt or killed, he has got a problem.
In this case, though, I think the key thing that led to the decision was that nobody knew how the Pirelli tyres were going to perform.
There had been hardly any running on them this year, none at all in Canada, and it is a high-speed track with walls everywhere.
Nevertheless, I think F1 should push the boundaries out a bit more, the safety car should be less in-vision and the drivers should drive to the conditions. The safety car should be a last resort, not a default option.
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