Douglas Harrington wrote:
"Bicycles stop on green". What is that supposed to mean? How are you
supposed to stop on green (and why the hell would you want to)?

These crazy zen signs are all over Eastern Massachusetts.

They actually read, "Bicycles stop *for* green" (emphasis added), but the
brain quite reasonably parses that as "on."

It is not a goofball local ordinance. It is not a strange way to say yield
or be careful or proceed with caution or anything like that. It is just a
very stupid sign.

I can't cite the source (though I think I read it in the Boston Globe), but
AustinMN was absolutely right when he or she wrote:

The intent is for
cyclists to stop on the line _when red_ in order to trip the sensor.

There is an utterly incomprehensible drawing of a bicycle and a dotted line
(where you are supposed to find the sensor, maybe) on these signs as well.

Armed with this knowledge, one can suppose that the word "for" in "Bicycles
stop for green" means "to bring about," not "on." (As in "Push button for
walk light.")

This has to be the stupidest bit of signage in a world overrun with stupid
signage. Monty Python-esque does not begin to describe it.