[CognitiveLens]

This is a major piece in the overall puzzle that the article doesn't really explore. Google's greatest strategic advantage is networked systems - each additional driverless car is a mobile, sensor-packed learning system for all other driverless cars. I strongly doubt that the plan is for each car to 'learn' how to handle each new driving situation independently - as soon as one car learns a behavior, they all learn that behavior.

That level of networked learning system is probably not fully mature, but it's certainly not far from reality.