steve@ace:Lane filtering can introduce some risk, but so can waiting in line if an idiot drives into the back of you - and I know from our customers that more of the latter accidents have happened that from lane filtering.
I agree with ColdCola...filtering introduces an element of uncertainty in the minds of road users (note, I use the word to include everyone, not just drivers/cagers). I also agree with you Steve....although do you think that people running into the back of a motorcyclist/scooter rider may have thought that that rider would filter and suddenly surprised when s/he doesn't? I've had plenty of near-misses when I've been on my pushbike, stopped at lights like I'm supposed to....only to hear the squeal of brakes behind me. Apologetic driver saying sorry out his/her window saying that s/he thought I'd go through the lights 'like all the other cyclists'.
That's not intended to be a general wide-sweeping statement. I've had enough experience as a driver to know what stupid things drivers can do...and in these days of mobile phones, invincible P-platers and L-platers. I saw a rear-ender last week on the approach to the Harbour Bridge....stupid driver thought that he could just jump into a gap in the traffic, the car in front (in the lane he changed into ) wasn't moving very fast and stopped suddenly...and bang, he hit the car.
I will probably succumb to filtering in extreme circumstances....but not right now. Not when I'm still on my Ls....and getting used to motorcyclists/scooter riders almost wiping me out as they ride through my lane and buffer zone. I can live with getting home 5 minutes later.