Iain writes: I moved to Portland, Ore., three years ago and love it. But drivers here refuse to zipper merge. Instead, they all jam their way into the continuing lane as soon as they can. As I drive by them to the merge point, they often try to block me from merging and/or flip me the bird. Please order Portland to get on board with the zipper merge.

You can’t change Portland. It’s a wonderful city, made so by its unique culture of tolerance, inclusiveness and punishing sanctimony. Yes, the zipper merge is more efficient. But cutting to the front of the line still looks like ... well, cutting to the front of the line — a particular affront in a city where they line up single file at bars, like kindergartners waiting for a snack of beer. It will be generations before people accept what you’re doing, and by that time, all the gas will be gone, cars won’t exist and Portland will have won.