My assumption is that the…

My assumption is that the purpose of an HOV lane is to encourage car pooling and thereby reduce traffic congestion. It seems that was expanded to also use it to encourage people to drive green (low emissions) vehicles.

I have not read a great deal on the research done to determine if motorcycles vs car use reduces congestion. But physics and instinct seem to indicate that it would be so seeing as a motorcycle footprint is so much smaller. So encouraging people to ride motorcycles supports that HOV initiative.

I am absolutely certain that motorcycles use a great deal less fuel in transporting a person than all but electric cars. And therefore encouraging people to ride motorcycles support THAT HOV initiative.

It would seem to me that this is a great idea.

PS: I do scratch my head a bit when I see a taxi there...how is that car pooling or greener? But maybe there is some other reason I have not yet heard?