Lorries in London, it'd be alright if cyclists just saw their point of view.

If you are a slow rider you should roll up to stationary traffic and sit behind the car you pulled in behind. What's the point of scooting along, risking being taken out by a left-turner when you are just going to get passed again? Fair-weather commuters anyone?

I adjust to the situation - if I'm filtering I will do it on left and right depending on where there's more room, where my next turn is, that kind of thing.
But, I grew up cycling in country and suburban Oz where the traffic is almost ALWAYS faster than you and you'd be a fool to be anywhere other than left-hand-side. It took me quite a while to adjust to the London way of passing stuff on the right and filtering through traffic. The car traffic here is so much slower than bikes that it makes sense to overtake on the right most of the time. I've been hit undertaking a line of right-turning cars when one silly bint decided she'd had enough of waiting and suddenly turned left into me without looking or indicating. In this situation I would always be undertaking (even with this risk) because there's no room on the right and cars are turning right anyway.