Added a Nobody asked section to WRITING.md. Copy includes a detail only if someone reading the page would ask the question it answers. Edge cases settled while a feature was built stay out of feature pages and other acquisition copy; they go in Help when someone could reach the situation, or only in code, tests and docs/. Added a matching check to the final editing pass.
Writing guide: leave out details nobody asked about
Added a rule to the internal writing guide: copy includes a detail only if the page's reader would ask about it.