as a cyclist in the US there's a very common scenario here, too - turning right, looking left, not looking into the turn and bam, cyclist at high risk.
TO CLARIFY - the situation i am most referring to is a cross street, where the car is perpendicular to your path and would be coming from your left as a cyclist.
At least in California, the car is supposed to take the bike lane rather than turning over the top of it. In this way the bike only ever passes the car on the left, and motorists (provided they look when taking the lane) are less likely to hit a cyclist if they fail to check their right-hand mirror again.
He might not have been downvoted if he hadn't said it, but it's not like it's a farfetched idea. In Toronto Mayor Ford practically made it a campaign promise to screw over cyclists, going out of his way (and incurring great cost) in order to rip out recently installed bicycle lanes. So it's definitely a political issue, and while there might not be actual bona fide lobbyists there are definitely voters who are anti-road-cycling.
From the sounds of it, an optional bike lane would be a marked lane that only bicycles are allowed to use, but where bicyclists can also legally use the other lanes on the same road.
Imagine the bike lane is on the right. Now if cars are moving slowly you as a cyclist will be passing them on their right ("undertaking"). This is unsafe near the places where cars turn right (across the bike lane).
1. A bicyclist does not need to stay to the right of the road when approaching a place where right turns are allowed (i.e. can leave the bike lane).
2. Vehicles are required to merge into the bike lane before making a right turn, otherwise it's consider making a turn without being in the rightmost lane.
Not to say I've ever seen a single car in the bay area correctly merge to the bike lane before turning. Any case where a bicyclist is hit by a car making a right turn should be considered "failure to complete a passing maneuver."
A complication is when a car (or bus at bus stop, or whatever) is parked in the bike lane, or immediately on the curb lane, just before the right turn lane. In that case, it becomes a lot harder to get into the bike lane before making a right turn, and in SF, is a fairly common situation.
If you're just worried about cars, it's fairly safe to make the right turn lane from that non-rightmost lane, since the other car is blocking any other car from approaching there. However, bikes (and sometimes motorcyclists, but rarely are they that suicidal) are going to come up, so it's still prudent to both get into the far-right lane and check on the right. That's the most common "cars turning right from non-rightmost lane" situation I've seen, though.
My biggest question about California road rules: what kind of vehicle is a homeless guy with a shopping car full of cans/etc.? Is he a pedestrian (similar to a pedestrian pushing a stroller), or is he a vehicle like a bicycle? What if he's in a lane of traffic, going down the road at 1-2mph (which is reasonable, since he would take up the entire sidewalk otherwise).
A bad idea perhaps, but legally required, at least in Denmark. Bikes are suppose to stay as fare right on the road as possible at all time. This means that traffic aren't mixed, which is generally a good idea.
Isn't that pretty much why you always cycle with the direction of traffic? As a runner, I've been told to run against the flow for safety but almost always run into these types of situations (which is why I mostly go out of my way to run behind the cars stopped at intersections.)
TO CLARIFY - the situation i am most referring to is a cross street, where the car is perpendicular to your path and would be coming from your left as a cyclist.