The story of the pilot who alas died while flying a passenger jet of course makes on think about margins of error.

As it happens, the other day I heard an account of a couple driving down the motorway where the wife as front-seat passenger suddenly realised that her husband at the wheel was no longer with her. Somehow she managed to bring the car to a halt safely, helped by another driver who saw her vehicle swerving and used his car to help nudge hers off the road.

How would you or I cope in such circumstances?