Cities, unlike hearts, are not improved by zero congestion. Pretty much the whole of Australia has zero congestion (unless you count the flies). Cities are designed to concentrate - or congest - human energy. They are less about moving through than being there; they thrive on bustle, busy-ness and friction, creative and otherwise.

Think, for example, of the proposal to retime street crossings to give priority to pedestrians. Such ideas have been discussed and squabbled over in Sydney for decades. The killer is that every second given to the pedestrian is a second taken from traffic and, much as we might wish to see "cars" as the opposite of "people", any slowing of traffic will be bemoaned as a worsening of already intolerable "congestion".