From the report https://static.googleusercontent.com/media/www.google.com/en//selfdrivingcar/files/reports/report-1115.pdf https://static.googleusercontent.com/

From the report https://static.googleusercontent.com/media/www.google.com/en//selfdrivingcar/files/reports/report-1115.pdf https://static.googleusercontent.com/media/www.google.com/en...: >Miles driven since start of project in 2009: “Autonomous mode” means the software is driving the vehicle, and test drivers are not touching the manual controls. “Manual mode” means the test drivers are driving the car. > Autonomous mode: 1,320,755 miles > Manual mode: 955,771 miles So it seems the cars are self-driving only half of the time! The answer to 1) seems to be driver takes over all the time.