exactly my point champ...the semi colon in 150 between a) and b) is an "or" which means in a multiLINE situation you are entitled to pass to the right of another vehicle without requiring the vehicle to the left to be indicating a left turn. Again I stress it is a multi-LINE situation not LANE. Meaning a wide enough lane sufficient for 2 vehicles is a situation where by one can legally pass to the right irrespective of signal inidication of the leftmost vehicle. This allows for filtering to the right of a vehicle, space permitting for a smaller motorcycle vehicle (which is classed as a vehicle).
A motorcycle is not a "line of vehicles."