All of the people tailgating are contributing to the congestion.
I don't drive as often as I used to, but on I-76 coming into or out of Philadelphia, traffic gets snarled and becomes stop-and-go. Every now and then, someone next to me appears to have the same understanding of fluid dynamics as I do, and we build up enough of a buffer that we are able to eliminate the stop-and-go, even if it means rolling at 5mph with a big gap between us and the cars in front of us.
There's no good way to communicate what we're doing, even to each other. But I like to think that when this happens, it has a positive effect that ripples out for miles.
Yup. The brake pedal is an evil device that converts cash into brake dust and waste heat. Before I got an EV, I always drove in such a way to use the pedal as little as possible. As a result, in my previous car that was stickered at 24 mpg city/30 mpg highway, I averaged 32 mpg. I don't even drive slow, I just drive smoothly. If your average speed is going to be 5 mph, then you'll get much better economy driving a constant 5 mph than your speed being a sine wave between 0 and 10 mph.
Good driving instructors make you aware of that early on, at least mine did.
I'm not saying that I'm a good driver, because I make mistakes like any other driver out-there, it's just that I oftentimes go with the "maximize the flow" thing instead of just following my individual "well-being" as a driver as a result of what my driver instructor told me some years ago.
Adam Something has a video responding to it that's worth watching too: https://www.youtube.com/watch?v=oafm733nI6U