But not there. I know it's required at faster corners, but that hairpin is one of the slowest corners in F1, and it's also a wide circuit. Tarmac run-off is not required there.
And if it was, it would be on corner entry for those missing the braking marker, not on corner exit. for those that hit the throttle too soon.
I find all this issue very simple, not much room for controversy. And I also don't agree that the Stewards or Whiting should need to tell a team to give up position or else ...
The Alonso/Kubica episode is very telling in this regard. Alonso asked the team if he should give the position back to Kubica, Domenicalli told him to keep as if nothing while they discussed the matter with "Charlie". Meanwhile, surrendering the position to Kubica became impossible because Kubica pitted. Well, a bit later poor old Stefano was on the comm telling Alonso that he needed to do a drive through.
IIRC, this was when Alonso showed Stefano that he wasn't someone to be messed up with. clearly furious, he asked for silence from that moment on until the end of the race. And the pit crew obeyed.
So, in this case, it's the same. If Vettel can't see what he has done, the team should instruct him. Not the FIA or the stewards office.
And another comment for those that think the penalty is too harsh. It isn't, penalties are not meant to "put things right", they are also meant to punish.
If the penalty was only a demotion to third, then what would Vettel lose for doing something wrong? Nothing. And what could he gain? Second place if the stewards looked the other way. Win-win to go off track then. Or at least win-no loss.
EDIT - First part of my post tree'd by hornet