Most places, someone who is keeping with the flow of traffic is a "speeder."
'Cause in a little while, they'll reach the start of the "clump" and pbutt the lead vehicle, and then be in the clear. This works, although less efficiently, even on fairly crowded interstate highways.
The "speeder" is, for maybe 50% of the time, traveling in the clear, no other car closeby. The person that catches a clump, slows down and joins it, is then traveling with people closeby 100% of the time after that.
And, while going just a bit faster than everyone else, the "speeder" is limiting his exposure from behind, where it's hard to keep looking without diverting attention from what's in front of the car. Those cars who are faster, and coming up from behind, can be seen and possibly avoided because it takes longer to catch up to the "speeders" car that is traveling faster.
Plus, those that are sitting in traffic, just doing what everyone else does, I find highly suspicious that they are not paying full attention. If they were, they'd be bored out of their minds, since there's basically not much to do when you do that. No, they are just sitting back, thinking of something else, and not concetrating on the traffic. OTOH, the guy that is going a little bit faster is concentrating on figuring out who is about to change lanes ahead of him, where to make the next pbutt, what car is likely to do something weird.
DPH
