A similar ordinance was proposed last June, but the city council rejected it 5-4, with the majority saying it was not willing to authorize the signs in bulk without gathering further information. Three city workers were then assigned to drive around and look at 2,595 signs and checking each one against a map to determine which were the 1,903 that had been officially approved. The mayor's office presented its report in November. Assuming the three sign-checkers started this project in July and finished at the end of October, that's about seven signs per day per person. It's tempting to say that this is not a very impressive rate, but I imagine they were all going a little crazy by sign number two-thousand...UPDATE: City to Legitimize Mystery Stop Signs, Report Says
A city official said they believed that the mystery signs had been put up by "housing developments over the years" that had not followed the right protocol to codify the signs. Translation: they have no idea. I prefer to think that they all just appeared one night, like crop circles, and so that's the explanation I'm going with.
I write books. My latest is a YA science fiction novel called Homeland (it's the sequel to Little Brother). More books: Rapture of the Nerds (a novel, with Charlie Stross); With a Little Help (short stories); and The Great Big Beautiful Tomorrow (novella and nonfic). I speak all over the place and I tweet and tumble, too.