NzBeagle:
joker97: How slow is too slow? When the car behind wants to get past?
I guess there would be some individual judgement regarding this, if you are below (-10) then you should be courteous. The question is then, what about the guy travelling 120 when you're going 100, well I think in the interest of allowing them to pass safely, i'd assist by pulling over where possible. I'm not the police, I can *555 them, but holding them up could lead to a dangerous overtake. You can be less courteous, in the form of the horn, flashing your lights, giving them the middle.
I think etiquette is the right concept here. If the guy is driving at 120 because he's bleeding to death from a stab wound by all means!