1. Everything you say could be true, and Google's solution could still be more efficient than tearing up 90% of the intersections in the US. 2. Retiming the

1. Everything you say could be true, and Google's solution could still be more efficient than tearing up 90% of the intersections in the US. 2. Retiming the traffic lights is an answer to a problem. Google's approach is only one possible way of getting to that answer. There may be more efficient ways.