edit: to slack - agreed on both counts
i think its the ability to "**** it up" and the degree to which it is fucked, which dictates the success of the writer. for example, Duffy is hailed as one of the best contempary poets, and the way she reinterprets old ideas, most notably in the world's wife, shows her consumate skill at writing from new, in her case mostly feminine, perspectives.
ironically yes it seems, star wars can be seen as original or a mich mash of westerns, and so on. but then, it brought new ideas to the sci fi genre, at least on a mainstream level.
there's a narrative theory, can't remember who's, that says there are several basic story lines, and all stories revolve around these. but then its the new spin the author puts on these that determines the originality.
to eliminator: proof?