Readjusting Mirrors Redux
: That way of readjusting mirrors is not new. It's in the official driver's handbook of Ontario. To quote:
... To reduce the blind spots, position the interior mirror so that the centre of the mirror shows the centre of the rear window. You should be able to see directly behind the car when the interior mirror is properly adjusted. Position the left outside mirror, by leaning towards the window and moving the mirror so that you can just see the rear of your car. Position the right outside mirror by leaning to the centre of the vehicle and moving the mirror so that you can again just see the rear of your car. Avoid overlap in what you can see in your mirrors. ...