There are even laws on the books specifying the left lane as the "passing lane". There seems to be a recent trend in making these more strict, so I wonder what effect they're having. This guy seems to have an up-to-date catalogue (green indicates more strict):

http://www.mit.edu/~jfc/right.html

In the UK it still is, and passing on the left is illegal. I like that system more that all lanes equal.

Took me a moment to understand because I forgot that in the UK the sides are exchanged. Left = Right and Right = Left in traffic. :-)

It is the same in Germany. I always assumed it was that way everywhere.

So if there is a slow car there, what do you do? Does everyone wait behind them until they turn/exit or decide to switch lanes?

If there's a slow car in the outside lane, and they're not making any attempt to overtake anything, you generally flash them until they move over. They are, after all, breaking the law.

What if a car is in the passing lane doing the speed limit? Asking them to move out of the lane so another driver could pass by speeding, breaking the law, doesn't make much sense either.

It's a grey area, although usually accepted that 90% of drivers drive faster than the speed limit anyway.

If it's a 70 limit, and someone is in the passing lane doing 70, you'd still flash them.

Speed limit on an Autobahn?

(OK, there are speed limits on most patches of the Autobahn. But there are some without.)

If he's driving at the same rate as the cars in the inner lane, he shouldn't be in the passing lane.

Yes. It's amazing to watch if you're used to driving in the US. You'll get an unbelievable amount of grief if you allow yourself to be approached from behind in the inside lane. Even driving in the center lane, you are expected to move outside if there is room to do so. Try driving there long-term and you'll get fast drivers cutting you off from the passing lane just to teach you a lesson.

And no, nobody passes on the outside. Even if you're about to exit and the rest of the lanes are moving slowly, you'll still slow down considerably and look a bit sheepish as you drift past the main highway traffic.

Occasionally idiots pass on the outside.

In Indiana and Michigan, left is a passing lane.

One problem here is that people driving the maximum lawful speed are still driving too slow for the prevailing speed of traffic.

So the difference is between "left is a passing lane" and "no passing on the right". In other words, it could be the slow car in the left lane that is breaking the law because it is not passing, just staying there, or it is the other cars that pass on the right that are breaking the law. I am sure the police would rather have both -- ticket those hanging out in the left lane and those passing on the right. Win-win for state/local budget!

There is no law against "passing on the right", at least not if this means "passing someone in a left lane while you're in a legitimate lane to the right of that vehicle".

For example, in the state of NY: Before you pass on the right on multilane roads such as expressways, make sure you check your mirrors, use the proper signals for lane change, and look over your right shoulder for other vehicles. After passing, be sure to check over your left shoulder, and to signal, before returning to the left lane. http://www.nydmv.state.ny.us/dmanual/chapter06-manual.htm

The thing that drives me nuts the most is slow people who stay in the left lane in the passing lanes that are sometimes put in on 2 lane highways (ie, 2 lanes going in the same direction for a time). Some states (Minnesota for sure) simply make a solid line to shunt drivers over to the right lane and it makes a huge difference, but around here (Wisconsin) they don't do that and inevitably I'll end up stuck driving 45 on a behind an old camper on a 2 lane highway because they refuse to keep right.

IIRC from drivers' ed, it's illegal to do this unless you're passing or preparing for a left turn.

perhaps if this was enforced more routinely it would help with the principles discuss in the article.