If a bike can safely yield, then this seems to imply that visibility is good enough to see coming cars. Wouldn't it then be safe for cars to treat it as a yield as well, especially if we consider that a car could likely clear the intersection more quickly than bike (aka the visibility distances needed for a bike to safely treat it as a yield are greater than for a car since they potentially spend more time in the intersection due to slower speed)?
Not really; in that case the stop sign should just be a yield sign. That's the point of this law: the margin where an action is safe enough is vastly different between bikes and cars. A car and a bike travelling at the same speed will cause vastly different amounts of harm on impacting the same object. The absolute time to emergency stop is different, thus the required reaction time. And so on.
"A car and a bike travelling at the same speed will cause vastly different amounts of harm on impacting the same object."
Theoretically, then the bike should be stopping. Two cars colliding at 15 mph is less dangerous than a bike hitting or being hit by a car at 15 mph. I doubt the stopping distances are that much different (probably 20 vs 30 feet).
"in that case the stop sign should just be a yield sign."
Well, most stop signs could just be yield signs. Looks like they're doing that for bikes. Would be nice if they do that for cars too.
> Theoretically, then the bike should be stopping.
As I and others have pointed out elsewhere, the law hasn't changed at all what a bike may or should do when there is a car present. It only covers the situation when there is no other traffic.
And that doesn't conflict with what I'm saying - that you have to have the visibility/design at that intersection to be able to see that there are no cars present; that if a bike can safely see that there are no other cars around and keep rolling, then a car could too.
The major hangups are that cars are inherently more likely to cause a collision and are significantly deadlier if a collision occurs. They have a much larger hitbox, they weigh several tons, they cannot maneuver easily and rapidly, they have visibility obstructions (like the A-block), and the internal environment of a car has potential distractions that take their attention off of the street. By contrast, bicycles are small, weigh an order of magnitude less, have no blind spots, and can execute dramatic maneuvers to avoid collisions. Cyclists should have the option but not the obligation to exercise additional restraint at intersections because their risk profile is dramatically different.
Stop signs are so common in North America because they serve as "bolted-on" traffic calming, which is necessary to force drivers to proceed at safe speeds and pay attention to their environment. In addition to vehicles within the intersection, you also have to look for people crossing at the crosswalks, and dedicated bicycle crossings if the intersection is so enlightened as to have them.
