On most US highways (i.e. multi-lane limited access roads), it's customary to leave a path in the left 'passing lane' for any traffic that wants/needs to go faster than you. If cars match speeds across lanes, it impedes faster traffic.

The speed limit itself is a separate convention and regulation. In some places you can be cited for obstructing traffic by going the speed limit in the passing lane if you are matching the speed of cars to your right, effectively blocking the road.

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FL410 9 hours ago | parent | next [-]

>it's customary to leave a path in the left 'passing lane' for any traffic that wants/needs to go faster than you

It's not just customary in many (most?) states, it's the law. People who sit in the left lane are the problem.

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eszed 9 hours ago | parent | prev | next [-]

> it's customary to leave a path in the left 'passing lane' for any traffic that wants/needs to go faster than you.

A custom that (where I live) is becoming more honored in the breach than the observance. It makes driving very much more dangerous.

In Britain they have a sardonic nickname for people who do this: CLARAs. "Centre Lane Residency Association".

	▲	rootusrootus 9 hours ago \| parent \| next [-]
		Sometimes I an appreciate wanting to cruise in the middle lane, because ADAS level 2 systems common on cars today is far more comfortable when it does not have to deal with regular merging traffic. But aside from that, I really don't like it when people camp in the middle lane because they tend to form a pretty tight line and manage to effectively turn a three-lane highway into two single-lane highways -- hard to get through from one side to the other.
	▲	circuit10 9 hours ago \| parent \| prev [-]
		I’m from England but I’ve only every heard “middle lane hoggers” for this

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rootusrootus 9 hours ago | parent | prev [-]

> If cars match speeds across lanes, it impedes faster traffic.

I think this undersells it a little. It does not just impede faster traffic, when the lanes are pacing each other it makes navigating harder -- simply switching lanes is more difficult. The highway moves so much more efficiently with a small but steady difference in speed between each lane.

	▲	saalweachter 4 hours ago \| parent [-]
		> Results: A 5-mph increase in the maximum state speed limit was associated with an 8.5% increase in fatality rates on interstates/freeways and a 2.8% increase on other roads. In total during the 25-year study period, there were an estimated 36,760 more traffic fatalities than would have been expected if maximum speed limits had not increased—13,638 on interstates/freeways and 23,122 on other roads. https://www.iihs.org/research-areas/bibliography/ref/2188