One commenter of that post noted:
Snake Eater said... But they left out "Stop When Red".I realize that should be an extension of "Wait for Green Light", but if you have to explain the green light, maybe you'd better explain the red one as well. - Link
A very good point indeed. And from the following photograph, apparently there is a need to explain how lights work in general.
The photo is from this Washington, DC Examiner Article 'Firm donated during traffic bid'
Maybe the masses are stupid.
Maybe they become stupid when you treat them as if they are.
Maybe the police should be encouraged to remove people who don't know how to drive from the road.