Who Is Passing Whom?

When driving, you should know at all times who is passing whom. The point isn't to know a current factual answer, such as “that other car is passing me at a relative speed of 0.01 mph”; the point is to have an intent in mind, to know how you expect the situation to play out. Once you have an intent in mind, you should of course act on it, with proper relative speed, but that's a separate issue.

Knowing who is passing whom is important, but it's also important that the knowledge be tentative and flexible. Sometimes you'll decide that you're passing another car, and start to do so, only to discover that you misjudged the speeds, that the driver of the other car doesn't want to be passed, or even that you just don't want to be going that fast. No matter the cause, you are allowed to change your decision.

If you're ever in doubt as to who should be passing whom, here's a fairly obvious rule I like to use.

Whoever is going faster should end up in front.

That reminds me of the following, which is an actual mathematical fact.

If you catch up to someone, you have, on average, been going faster.

That's what I wish I could say to all the oblivious drivers who catch up with me but don't pass. (Well, that and “hello?!?”.)