Re: pretty much universal adoption
It doesn't actually have to be universal adoption. I'd think you might see some changes with as little as 10% adoption and significant change at 50%. Traffic tends to move in slugs. If you are moving in a slug and looking at the car in front of you instead of a car three ahead in the slug, you'll never have time to react to a sudden changes. Depending on the exact range of "short range" that would give you three cars and so long as one of them gives you warning, you can adjust based on the tech. At 50% adoption and even distribution you'd only have a 13% chance that none of the cars would provide data.