Right. Because having to sit in the cab of a locomotive and watching as you are about mow down a human being, knowing that you've dynamited the brakes and the laws of physics are going to give you a front row seat to a collision between 120 pounds of flesh and thousands of tons of metal, will have no emotional effect on you.

I've had friends who've had to leave that profession after a crash like that, and they replay the moment in their nightmares.