R1 if you mean by weaving up the motorway you are implying the drivers who pull into the nearside lane when it is clear and then pull out again to pass slower moving traffic I think you will find they are driving within the rules of the road. The inside lane is the normal lane, any other lane on a motorway or multi-lane carriageway is purely for use while overtaking slower vehicles. Amazing how many people think the inside lane is for trucks, middle lane is for slow cars and the out side lane is for boy racers and reps!!!