I had a slow realization that I could just let people jump in. My goal is to maintain a constant speed and never have to hit the brakes, and I can usually still do that regardless of whether people jump line.

But yes, the principle of it is incredibly aggravating ("that space is for safety, not YOU, green Acura!!!") but I actually kinda like the practice of trying to be zen about it. I mostly get through a long trip at the same rate :)