Let's not overlook that once a single self driving car understands these local, informal rules, ALL self driving cars will. That's about a million times better

Let's not overlook that once a single self driving car understands these local, informal rules, ALL self driving cars will. That's about a million times better than the current situation where every new human driver has to learn them. I was going to use a number smaller than a million, but 10k or 100k doesn't seem to properly describe the situation. Literally, these systems will be hazards until the day they aren't, and then they will, for all cars, forevermore, be better than every local.