This was interesting - driving maybe 70 mph with one hand, guessing where the camera was pointed and shooting with the other hand.
But this came out exactly as I wanted. The car keeping behind me is sharp because it was going the same speed (you can read the license plate at full size), and the distant landscape is also sharp. Only the middle distance is blurred by the speed.
When he finally passed, I quickly put the camera down. I wouldn't want him thinking I'm shooting pictures instead of concentrating on driving!