Some ideas are so well-worn that they simply can’t be used anymore. At least, they can’t be used outside their original context. Take the Arthurian cycle, for example. There is no possible way to use the Arthurian model to “shade” another concept without causing such a massive fit of eye-rolling as to blind your potential audience or group. Nobody wants to hear about your retelling of Arthurian legend in the context of Tony Blair’s and Gordon Brown’s England. Nobody wants King Arthur vampire stories, no matter how well the title “The Once and Future King” would apply to such. (Actually, there’s probably a buyer for it in YA fiction, given how voraciously that market craves vampires right now, no matter poor the treatment.) It’s too beaten an idea to be taken seriously unless you’re telling a story of the straight-up King Arthur. Not a reincarnation. Not an allegory. Not a time-travel story. Bog-standard King Arthur is all that’ll fly.And then there’s the weird case of idea incest, which turns the original idea back toward itself in a Mobius strip of experience. Look at D&D. D&D influenced every goddamn computer RPG out there. Even video games outside the RPG medium have concepts like “hit points” that originated with D&D. As the hobby spread, the player base for video games eclipsed that of tabletop hobby games in general — but that’s not the weird point. No, D&D was the pioneer, the foundation upon which a lot of computer gaming was built. The weird point is that now, fourth-edition D&D actually emulates the video game experience. That’s not necessarily a bad thing, and I understand why the design was done the way it was. No, to me, the weird part is that it’s become its own grandchild. It’s like dating a girl, then breaking up with her and dating someone like her, and then going back to the original girl who has done as much as she could to adapt the style of the girl you replaced her with in hopes of winning you back. Is there some Oedipal thing happening here? Some nerd-version of Freud? Now, don’t take this as a bash on D&D. Fourth edition works well and is easy as pie to run. But it’s no longer very similar to its initial incarnation.