Some advice. Do NOT tell anyone to pull over teach them a lesson - it can be used against you in a court, should the circumstance arise.
I'm not saying the person wasn't being a prick, if what you say is true. You have every right to be angry. But why give them an inch with which to take a mile? Use the horn and get clear of the immediate danger.. challenging
This isn't even a case of using mirrors, it's a question of being such a uniquely incompetent driver that you can't even stay on the road made for you.
It's a good question how an idiot like him passed his test, if he ever even did.