When driving down the notorious A11, particularly before it was duelled, I would often be bemused at the occurrence of traffic jams when there were no road accidents and no maintenance work to hold up traffic. I would tell my wife what I was thought was going on - it's what I call the 'flow' factor being interrupted. The flow is how I describe the optimal driving process, whereby when there are no obstacles, if all drivers filter in, speed up and slow in ways that do not impede the natural movement of other cars they are not interrupting the 'flow'. An optimal driving state would occur when no one is made to slow down, speed up or stop against the flow.
As drivers we obviously need to slow down and stop for all sorts of reasons (traffic lights, junctions, roundabouts, queues in rush hour, etc) but a lot of the unnecessary delays are caused by the natural flow of driving being interrupted by people who brake more than they need to. Clearly, with short distances in diversely planned cities, small interruptions are minimal and don't really register on the radar (unless you are a particularly irascible and impatient driver), but on long A roads (like the A11) and motorways careless interruptions to the flow can result in long traffic jams, caused simply because someone was too heavy on the brake pedal.
I was pleased to see this week that there's actually a video which proves my 'flow' theory - it explains how one driver hitting his or her brakes too hard can slow everything down and cause a huge tail back as it sets off a ripple where cars behind it also need to brake until at the end of the chain reaction, traffic has come to a stand still. Naturally, even when cars start moving at the front, by then the tail end of cars is sufficiently halted to see numerous cars joining the back of the tail, and so it goes on, taking ages to clear.
Here is the video- it's the second half that is most compelling. So, from now on, drivers, please do go easy on the brake pedal - for all our sakes.
