Over the past few seasons there have been many occasions where F1 race stewards have failed to take excellent opportunities to do nothing. Spa 2008 comes most readily to mind, but there are plenty of others. At Interlagos they took that opportunity with an incident that was crying out for their involvement.
Let's not be too hard on Kamui Kobayashi. He was driving in his first grand prix, he'd done brilliantly to withstand many laps of pressure from a world title contender snapping at his heels, and generally gave an impressive account of himself despite very little preparation. But his move on Kazuki Nakajima that took the Williams out of the race was outrageously dangerous.
Kobayashi was just coming out of the pit-exit road as Nakajima - with whom he'd been battling all race - was bearing down on him with more momentum. Ahead was Turn 4, a key passing place.
Kobayashi really needed to be hugging the left-hand side of the track at this point to prevent Nakajima getting his nose in, but a moment's inattention allowed the Williams in. At this point it would be acceptable racing etiquette for the Toyota to move over a little on the other guy, to try to make him think he hadn't seen him or to intimidate him into backing out of the move.
But once you've reached a certain point, leaving him only the room he absolutely needs to stay on the track and not an inch more, you are not entitled to keep moving across on him. Especially when that guy is so far alongside you he cannot back out of it. But that's what Kobayashi did, squeezing Nakajima onto the grass and into the barriers flat in seventh gear. Kazuki had a big impact into the Turn 4 barriers from which he emerged unharmed, but he could so easily have interlocked the Toyota's wheels and gone end over end.
The stewards didn't even see fit to investigate the incident. So now Kobayashi has every reason to feel that what he did was acceptable. It bloody wasn't; it was lethal!
On the first lap of the race, Mark Webber was involved in a very close call with Kimi Raikkonen into the same turn that took off the Ferrari's front wing. "I was firm with him," said Webber afterwards. "He would've done the same to me." As the KERS-assisted Ferrari was closing him down, Webber had made his permitted one move, moving to the inside, and stayed there as long as possible before making his allowed move back onto the racing line before the corner.
As far as Webber was concerned, he'd driven within the letter of the rules and it was up to Raikkonen not have his front wing in the way as Mark swept back to the outside. Webber consistently takes the accepted interpretation of this rule to the limit - see several of his moves with Fernando Alonso over the years, or that on Felipe Massa at Fuji last year. They all make you wince, and he's sometimes even summoned to the stewards' office afterwards, but he doesn't get nailed - and rightly so, because he's always just this side of legal.
But maybe it's time to look at changing that interpretation. Once all the others begin taking it as far as Webber, some of them not so fine in their judgment, it could get very dangerous. If Kobayashi's move was seen as acceptable, then all bets are surely off. Maybe it's now time to insist that you're allowed just one move, and once you've made that move you can't then deviate until after the corner. Yes, it makes you easy meat to a faster car bearing down on you. But you'd then have the same opportunity to do it back if you're fast enough.
It would increase overtaking, it would bring in a different element of racecraft - and it would be a damned sight safer. Besides, the racing etiquette of F1 funnels down to all the single-seater categories, and that is not a reassuring thought with the interpretation we have.