A while back, I put out a word fugitive for a term that would capture this driving tactic -- when you need to change lanes, instead of getting into some kind of accelerating, aggressive drag race to get over, just hang back, let the car alongside you get ahead, and then skoinks your way into the lane you need. Chris Amatuzzi came back masterfully with "rope-a-dope."
For instance, you could say, "The lane to my right is just way too jammed up and there's no way I can get in. I'll just decelerate, hang back and then rope-a-dope my way over."
Rope-a-dope can be used as either a noun (describing the tactic itself) or as a verb. It's a great expression because it's easy to remember and use, yet it also *sort of* describes what you're doing -- accomplishing your goal by doing something somewhat counterintuitive that surprises others around you.
Another one that I'll throw out there is called "The Ultimate Awful."
Here's how it works: You're on the Interstate and you need to get over for your exit. Being the conscientious citizen you are, you check your mirrors and then give a quick visual to ensure the nearest vehicle in the lane you need to get into is several car lengths back. You signal to announce your intentions (again, doing the right thing) and what does the psycho behind the wheel of the other car do? Accelerates as if you getting into that lane will unleash nuclear armageddon.
I have absolutely no idea why people do this, but I think it must come from some place of raw aggression borne of an idea that one person's gain must be another's loss. In other words, they're thinking, "If you get into that lane, you're somehow 'getting ahead' and I will suffer."
I call this 'The Ultimate Awful' because I think that type of zero-sum, tit-for-tat, fight-for-every-square-inch mentality is just rotten. I know I'm *only* talking about driving but there are tons of other ways this mentality manifests itself in our daily lives. My hunch is that people who practice 'The Ultimate Awful' probably behave in many other ways that are, well, ultimately awful towards their neighbors, co-workers, and families.
And on top of all that, you're talking about huge, heavy boxes of steel and glass moving at high speeds. So it's not just like the un-neighborly rudeness of not looking behind you when you walk through a door -- it's a whole new level of rudeness when you factor in the completely unnecessary level of danger you're creating.
So that's how it earns its name.