I wondered during the race: why were they allowed to put the car back on track after the 'retirement'?
Is there really no rule to stop that? Like could you conceivably crash, be brought back to the garage, repaired, get back in and rejoin the race? I guess there's little reason to (excepted in a contrived situation like this), but I'd always assumed that was not permitted.
As long as the driver and the car can get back to the pits on their own, I think yes. When crashing out you'd likely need external help to get back to the pit lane, so I'm pretty sure you'd be out for good then.
Yeah I'd always assumed 'external help' would be the dealbreaker, but I checked the onboard and you can see they jack the car up on to the 'skateboard' to move it back in to the garage (00:37 on F1TV feed). Perhaps it's external powered help, I guess that would get around cars being pushed back by marshals too.
team can help. I think the "skateboard" is not considered different than the jacks, or even wheel guns for that matter. The Team is allowed to use tools on their vehicle during a pit-stop.
Long ago, they used to have spare cars for just such an occasion! My question is: if a safety car happened during his one lap, would we be required to watch checo unlap himself for 26 laps before going green?
Well it used to be the case on purpose, given that they had third cars for the scenario of a crash. And then everyone simply forgot about how it was and wasnt covered by the rules, I guess.