What about passing in between the vehicle and the white lines ( only if there is sufficient space though eh ) ?
Do the double whites mean " No Overtaking " or just " Do Not Cross " ??
They mean 'do not cross', so yes if there is enough room then you can legally still overtake and be within your side of the line. When I did my bikesafe course a few years ago, the copper said its ok to overtake/cross the white lines if the line of traffic is stationary, however once it starts moving again, then you must get back inside the white lines.
+1
Though be aware that crossing means any part of YOU or the bike, so make sure you keep your elbows tucked in !
Personally I say it's a judgement thing, like all those max speed for signs you see on some bends, they're set for the lowest common denominator & you can often quite safely overtake single vehicles or small groups of cars on a bike where trying to do it in a car would be plain stupid. That said, plod do tend to have a very low leeway threshold on such behaviour.