First one. Around here, a school bus on a divided 4 lane highway only requires folks on the same side to stop for the flashing lights, the folks in the opposing lanes don't need to stop. Yet there are folks in the opposing lanes who will stop for the school bus anyway, so I (and many others) fly by them while they shoot dirty looks at us.
I've learned that if there's a power failure or malfunctioning traffic light at a major intersection, I try to avoid them like the plague. A shocking number of folks seem to forget to treat it as a 4 way stop and they don't stop at all. It's still chaos among the ones who do stop.