I had heard of traffic waves in congestion, but this phenomenon happens on open roads. I often notice vehicles forming packets when there isn't traffic. Like natural clustering? If I drive the speed limit, cars will start to bunch up behind me, even when there is an open lane. Then, a driver will speed up in the passing lane, but when they reach me, they often slow down slightly or a lot and ride next to me without passing.
I noticed a similar phenomenon while driving on the highway. Vehicles on the other side of the road seem to group up and travel in clusters. Like traffic naturally oscillates into these packets?
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