I always started off with "Good afernoon sir, I stopped you for speeding." That way if he had just killed his wife or something, he might figure that I was just going to write him a speeding ticket, and not try to shoot me while I was busy writing. That was how I was trained, and it worked for me. I would then ask if he had any idea how fast he had been going, the truthfulness of his answer had a direct bearing on how much of a break I gave...