Here's another counterintuitive truth to Lean: the more often you stop, the more smoothly things will move along. The caveat is that these stops should be small stops, as early and as far away from the actual problem point as possible. This makes sense when you think about the fact that you can correct and recover from small stops more quickly than you can from big, near catastrophic stops.

An article today on the science and technology news website physorg.com titled Traffic jam mystery solved by mathematicians refers to new research based on a mathematical model that shows that slowing down below a certain critical speed to avoid a collision can have a chain reaction effect on the cars after it for miles. If you are driving and there is a sudden traffic slow down and no accident to be seen, this phenomenon may be the culprit.

It is less an issue of volume of traffic. The article says:

"...the main issue is around the smoothness of traffic flow. According to the model, heavy traffic will not automatically lead to congestion but can be smooth-flowing. This model takes into account the time-delay in drivers’ reactions, which lead to drivers braking more heavily than would have been necessary had they identified and reacted to a problem ahead a second earlier."

Early detection of problems, smaller corrections, small effects to the people or processes downstream, and the implication that a bit of a buffer may be needed between. In driving school I was taught the 3 second rule (another rule of three!) of spacing to allow between your car and the car in front of you. This seems very practical now, though it's not always followed. In work, as in our driving, we push, thinking that this helps us get to where we want to go a bit faster, when in fact just one person pushing too far and causing someone to stomp on the breaks can slow us all down.