Pro: In any country except the USA, "tartan" is the pattern and "plaid" is the piece of clothing (something like a sash) that the pattern is woven into. Changing the name would make the wiki ever-so-slightly less America-centric.
Con: It would take a lot of work on both this page and others to fix the name.
Thoughts?
It's not just plaid/tartan that has this happen, right? If it happens to polkadots or crosshatching as well, why not call it "Unmoving (Clothes?) Pattern" or something, and leave Unmoving Plaid and Unmoving Tartan to redirect to it.
Good point. I like "Unmoving Pattern", since the trope sometimes appears when the clothing moves but the pattern doesn't.