All this depends on circumstances as said. As long as you are driving leagally then no-one can force you to do anything if you don´t want to (Emergency and Police excempt of course). If I can move ove or slow down a a certain point to allow -Mr in a hurry- to get by then I will. But I decide not him. Dangerous driving is just that. No one forces you to overtake dangerously just because they won´t go fast enough (in your opinion). Again it is up to the driver to do what they think is right as long as they are within the law. You can get done for going too slow in Germany I believe but not in UK as I understand and certainly not in Sweden. Over here there is a recomendation that you should pull over to the hard shoulder if it is safe to do so and let traffic by if you think that they want to and if YOU think it is safe. I don´t tollerate bullies and there has been a few craked heads over the years because of it (and not mine).
Over here you are welcome to ring the police and report dangerous driving with car and number. They keep this info for future reference. So if 20 people ring inabout one numberplate and that car subsiquently gets into an accident where word is against word then the 20 who´ve rung in could be used as a -characte reference- against the nurd. I´ve done this with lorry drivers. Works quite well
A car is firstly a deadly weapon and should be treated with that in mind
