And that's precisely my point. We're not talking about a hypothetical, all-bets-off thought experiment that is completely open to interpretation and debate, but a factual scenario that can be properly described and predicted.
If you sent your student away with the message "go and find out for yourself", what would you expect them to find out? If they've just been arguing that lead would make a better material for skyscraper construction that steel you would expect their experiments to back up what you'd told them, that they are talking out of their hats.
Well, I'm in the same situation. I could show you bends where, at linespeed, an obstruction would come into view giving sufficient time for a "bail out" but not sufficient space to avoid a collision, just the same as I could show you bend where this would not be possible. However, as I am unable to provide you with the opportunity to do this, would you at least accept my word on the matter, as a professional train driver?
O L Leigh