No rule will prevent all collisions of automobiles driven by humans. There's no free lunch here. If you want to be safer, drive less. TFA is fun, but mostly because it pretends that cyclists don't exist. IRL, there is a trade-off between turned-head blind spot checks and hidden-pedestrian alertness. You weren't talking about that trade-off, though. You were assuming that you always keep perfect track of your mirrors. Safety experts are quite sure that you don't.
