> However, in reality, the flow is constantly exposed to small perturbations: imperfections on the asphalt, tiny hiccups of the engines, half-seconds of driver

> However, in reality, the flow is constantly exposed to small perturbations: imperfections on the asphalt, tiny hiccups of the engines, half-seconds of driver inattention, and so on. I could see this — random imperfections and subtle movements of drivers causing someone to back off or brake. (I've definitely noticed other drivers being fearful of other drivers solely through their positioning on the road.) Engine hiccups sounds a bit fishy; does that happen to people? That said, I've also witnessed drivers with several hundred meters of open road in front of them — sometimes road as far as the eye can see — inexplicably brake. I've always wanted to ask them why. > Those who drive preventively can dissipate jamitons, and benefit all of the drivers behind them. I think it mostly boils down to listening to your driver's ed teacher, if you had one. Leave following distance. Other drivers tend to make this exceedingly hard, but if you can keep enough, you can keep your velocity relatively stable (and hopefully everyone behind you's velocity, too!) even when the car in front of you is doing a lot of braking and accelerating. I do it just so I don't have to move my foot so darn much in a traffic jam. Likewise, if you pay attention to how much following distance exists in front of the car in front of you, you can predict fairly well when that driver will need to brake and how hard. If they're tailgating, you'll need a larger following distance yourself if you don't want to tap the brake when they brake. I also use this when traffic looks like it's speeding up again, and I might want to close the gap in front of me a bit — I take into account how much of a gap is in front of the guy in front of me, to see how likely he is to brake while I try to catch up to him. …of course, these are just my experiences.