That's what I call those car/truck drivers who see a RR the same way a bull sees a matador's red cape. For whatever reason, the motorcycle seems to enrage them and they feel the need to get as close to your tail as possible. Speeding up is the worst solution, if they're inclined to do the same. Pulling over is the sensible thing to do, and let 'em go. Engaging with someone in possession of less than a full deck is a losing proposition.
Has this happened to you? Why do you think it happens?