Whilst I was typing away, many wiser heads raised many good points. But reading them all leads me to the one big question that eluded me in my ramblings. If a tartan is meant to denote IDENTITY, then one user is enough, but if it is meant to signify BELONGING, then there ought to be some minimum number of users or adherents before it really makes sense. I don't know that it is necessary to police that idea, but I think it is a useful one. Maybe then, somebody needs to ask

DOES ANYBODY CARE ABOUT THIS TARTAN?

Like a puppy, it needs someone to love it.