I’d go even farther and say most driving is an edge case. I used 30 day trial of full self-driving and the results were eye opening. Not how it did: it was pretty much as expected, but looking at where it went wrong.

Full self driving did very well in “normal” cases, but I never realized just how much of driving was an “edge” case. Lane markers faded? No road edge but the ditch? Construction? Pothole? Debris? Other car does something they shouldn’t have? Traffic lights not aligned in front of you so it’s not clear what lane? Intersection not aligned so you can’t just go straight across? People intruding? Contradictory signs? Signs covered by tree branches? No sight line when turning?

After that experiment, it seems like “edge” cases are more common than “normal” cases when driving. Humans just handle it without thinking about it, but the car needs more work here