Exactly. I'm a Rhiannon supporter, big time. OK, 90% of myths may be relatively recent but who is to say that they all are. I remember kids in my school playground repeating stories about local landmarks. That's what kids do, generation after generation. Who is to say- and why - that the odd one or two aren't the authentic voices of Iron Age or Neolithic people, handed down again and again? Why wouldn't they be, kids are the ultimate conservatives and never change their behaviour and rituals.
More folklore please, much more. It should be a central scientific part of the study of ancient sites (lets face it, conventional investigations haven't exactly provided all the answers).