Agree 100%, unless you've got all your ducks in a row, with all the correct paperwork done and all the remedials you can give done, even a student who (without seeming to be harsh), is a danger to himself and others has got a reasonable chance of having another go at it.
Saying all that, I think I get more nervous waiting for my students to finish tests and pass them than they do! If you're not there to instruct and try to get them through, you shouldn't be doing the job. So how the 'screaming skulls' of yesteryear did it I'll never know
One final point-
ng EDO's