Thank you dannmer for this information, which I think resolves this note, as well as ceyockey for documenting the issue and CurlingMan13 for input.

All: I'd appreciate input on the tunnel=culvert wiki talk page since I think there should be some guidance regarding this sort of edit.

https://wiki.openstreetmap.org/wiki/Talk:Tag:tunnel%3Dculvert#Inferred_culverts_to_avoid_editor_warnings

I have not specifically linked to this note or edit on the talk page, since I think ceyockey is editing in good faith, and this edit is only the exemplar of a broader behavior, generally practiced by people who don't leave notes about it.  I've added a lot of NHD data in South Carolina and the little culverts proliferate quickly afterwards.