I thought (ie taught by my IAM dad) it was generally acceptable to undertake in non free flowing conditions (i.e heavily conjested) as it is far better to stay in lane to not make the conjestion worse.
However my definition of not free flowing is not speed-dependant- if everyone is limited to 55 (by speed limit or by conditions) in heavily conjested traffic, I'll crawl past the middle lane in the inside lane. My friends don't seem to get that everyone doing 55 isn't normal motorway conditions, they think it off too farfor a queue...
Am I doing a bad?