LogFAQs > #972306911

Okay I will grant that a busy multiple-lane highway is different - which is because the status of how many cars are behind you DOES change frequently and those cars can try to pass you suddenly.

So that's really the answer to my question. Do you expect that there's a good reason for cars to be coming in and out from behind you, and that that could present a danger for you? If yes then you should be monitoring the mirror - if no then there's no reason to. It's completely dependent on circumstance.

Even on an interstate though, 2-3 seconds is probably more fretting over what's behind you than necessary - in most cases you'll probably coast with the same car behind you for a while. It's more than enough. I don't really know how often I actually check the mirror - it's basically second nature at this point that it would be like asking me how many times a minute I breathe in an out, I'm not thinking about it. That's really my main criticism with the "2-3 seconds for checking the mirror" thing - if you are thinking about it that much, you are probably overprioritizing what's behind you which means you are distracted from what's in front of you, which is hands down going to be what causes 99% of accidents.