Thanks. I appreciate the mention.
Out here in California during rush hour the diamond lane remains under-used while the other lanes are stopped dead in their tracks.
I’ve seen three lanes going around 25 mph, with a diamond lane with very few cars going by.
It doesn’t take a rocket scientist to figure out increasing the flow by opening up that diamond lane would ease traffic significantly.
My wife and I never used the diamond lane even when together. The folks in there want to go 80 and it gets to the point it’s unsafe to drive in there even at 70.
actually, in the state you mention, 3 lanes going 25, one lane let’s say completely empty, opening up that lane to all traffic would make only a minor change in total flow.
And that is even if we assume that a “2-person” rule has been useless in encouraging anybody to double-up.
IF you assumed that the 2-person rule was useful, and that eliminating it would make the 2-person cars into 1-person cars, then “opening up” the lane,even if it has only 10% of the traffic of the other lanes, doubles the traffic in that lane before you add anybody from the other lanes.
The question is why more people don’t double-up to avoid that 25-mph road situation.....
Here’s an interesting thing. If you presume people will follow the 1-car-length per 10 mph rule, and you compare a “fully packed” lane going 25 mph with a “fully-packed” lane going 60 mph, on the 25 mph lane you get 25 cars per minute past a point, while in the 60-mph lane you get 30 cars per minute.
In other words, even if people give the correct following distance, if you have a lane moving 25 mph, and you can FORCE that lane to go 60 mph, you’ll actually “thin out” the number of cars in a lane by 5 cars per minute by pushing them faster.
Meaning that the only reason they go slower is because the lane is overwhelmed. On the other hand, it shows that if you push more than 5 cars more into that lane, than the 25 on the other lanes, it will slow down to 25 mph.
There’s also a theory of road management built around this, that if you can slow traffic down just a little bit, you can get more cars through per minute, and avoid the overfull state that causes traffic to grind to a halt. This theory is being successfully used with some roads where they put speed limits every tenth of a mile for each lane, and if everybody obeys them, traffic moves quickly and smoothly.