Scenario 1:
moving to lane 1 would be the most dangerous thing here. moving to lane 3, well no 1 wants to do that. even though these daewoo drivers are on a tight schedule, that still dsnt mean they expect u to just fly off.... so id say just keep in ur lane, maybe increase your speed a tad bit to over take the trucks and let the daewoo bus overtake u on the 3rd lane. keep urself safe and out of danger. U have to hope that the daewoo driver has enough juice in his head to realize the situation and not drive over you. If u ever come across such a driver, note down the bus reg# and time, give daewoo a call a file a complaint against their driver. The reason why people travel by daewoo is because their buses and driver are safer to travel in and with.
Scenario 2:
With time, we all mature up. Atleast most of us. I used to do somthing wrong and i stated that here on this thread. I would start going parallel with the car in lane 2 when i was over taking him everytime a nutter like this would approach from the back in lane 1. These people have no sense and they dont care much. trust me, its annoying and dangerous especially when they start tailgating you. if you cant overtake the car in lane 2 fast enough and you know the lunatic will be on ur tail before you have safely overtake the car and moved back into lane 2, its advisable not to make the overtaking decision. leave that for after the nutter has passed you.
iv seen people who wont move to lane 2 and keep travelling in lane 1 even when there are 4-5 cars behind him that want to overtake. seen cars racing on the motorway and zig zagging. and worst of all, the tailgating issue.
moving between lanes is definitely not advisable, but just leave urself with enough room to save urself if God forbid somthing does happen.