I find if I drive at, or slightly above/below the speed limit, I collect cars behind me. If I drive 10-15 MPH under the speed limit, people usually pass me right away.
If there are no passing opportunities and I'm collecting cars, I'll increase my speed up to the posted limit. Or take a different route if possible.
I've learned how to get people to pass me. Most drivers won't pass right away. They need to be stuck behind me for a bit before deciding to pass. So I adjust my speed and let them catch up to me before entering a passing zone. I'm not sure if their hesitation to pass is because they assume I'm going to speed up, or the anger needs to build up to passing level. Either way, I've gotten good at making people pass me at the right time. I'm always looking for passing opportunities for the cars behind me. I might know when they're going to pass before they know.
