(Temporarily translating the drive-on-the-opposite-side-of-the-road thing back again, and making the point that traffic laws vary from state to state so I can only really speak for California...)

No, that's an incorrect assumption. If you ever go driving in California, if you look closely, you'll see the "Slower Traffic Keep Right" signs posted even on 6-lane freeways. So the laws are the same here in the states as they are in England, and they apply to freeways as well as highways.

Actually, this isn't correct for California, which really surprised me when I discovered it. In California's driver manual (the relevant section of which is accessible here), it explicitly says:

Pass on the right only:

- If an open highway is clearly marked for 2 or more lanes of vehicles moving in your direction of travel.

- If the driver of the other vehicle is making a left turn.

(it goes on to say other wonderful things).

This basically gives California drivers free reign to pass in whatever lane they dang well please (the only place you're required to pass on the left is a road where you have no choice, except if you're silly enough to want to use the shoulder for passing!) - despite the "slower traffic keep right" signs which are, in fact, posted quite frequently on most major freeways. This, I think, is a primary contributor to the terrible traffic I see all the time here in the L.A. metropolitan area.

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Daniel M. Zimmerman
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