Yeah I was a bit younger then and had a bit too much ill-founded respect for some older long-in-the-tooth riders I hung with lol.
As far as filtering is concerned, while I assume they have their reasons, that's just plain madness to me. The main reason I used the bike for the commute was because I had a 12 mile ride into/through the city which took about 15 minutes by bike, or around an hour (and sometimes more) by car. Not only that, but bikes are supposed to reduce congestion (part of the reason in the UK you pay a 1/4 of the road tax), if you treat them like, or apply to them the same laws as cars then you achieve nothing...? Not only that, but filtering was one of my fav parts about riding (my commute was almost ALL filtering), I cant imagine not being allowed to.
If the traffic is moving under walking speed I see no reason why bikes shouldn't be allowed to do what they're good at. Granted, after driving here in the states for the last 2 years I've noticed there is much much less lane discipline/awareness here (and more specifically its much less enforced by the authorities), but at under walking speed, I don't see how it could pose much of a threat to the rider or others.
I knew in some states it was illegal, but i had no idea it was so widespread. Oh well, we had actually been thinking about heading out to Cali at some point in the future anyway lol.