I suspect that the prevalence of two-lane Autobahnen has encouraged better lane discipline: people move out of lanes 2 (and 3) much more readily than in UK to let faster traffic through. The other major rule improving traffic flow is the overtaking ban on HGVs at peak time.

The other major rule improving traffic flow is the overtaking ban on HGVs at peak time.

That would be a good idea for the UK to adopt ...

It was adopted on parts of the A14 - with excellent results.

In comparison, driving on the USA 2 lane dual carriageway i-states is much more relaxing than on our dual carriageways/motorways for two reasons.

Firstly, everything, including even heavy semis with an additional trailer, goes at virtually the same speed - around an indicated 70-75 on the ubiquitous 65mph limit -up to 75 in remoter states. (imagine that, gb!). There are no slowcoaches dawdling at 60mph to save tuppenceha'pny. Indeed, around cities many have minimum speed limits of 40mph.

Secondly, although it's etiquette for slower traffic to stay in the inner lane(s), overtaking is allowed in any lane. It really is about time we adopted this as it makes for a much pleasanter driving experience. There is no concept of 'cutting up' and at busy times all lanes are occupied resulting in greater throughput.