> You're right. I've pushed the corrected version.  I tried testing with
> benchmark-run and the same large collection. The time fluctuates too
> much to judge which method is better. They're roughly equal, and the
> intuition is that not using `nreverse` is better.

If there were no notable speed differences, I'd say the nreverse version is shorter and easier to read. But I don't want to start bikeshedding, so feel free to disregard my opinion.