In the hope of gaining something academically useful out of what otherwise might (have already) become a sort of mud slinging fight, I would like to mention the now increasingly well studied area of "text reuse." 

Of course, this is in part behind the project of E. Prets, and it is conceptually behind plagiarism detection software etc., but it should be noted that there is considerable work being done with regard to Classical Studies, and to my knowledge (I'm not sure if this has been published yet) on Arabic World Histories. I myself am interested in this approach to what I see as the modularity of Buddhist scriptural literature, although the notion of modular composition is not exactly the same as text reuse as generally understood.

For a general overview of 'historical text reuse', one might see as a start http://etrap.gcdh.de/?page_id=332

I mean here only to point out an additional resource (not the website in particular, but the notion) to frame this discussion in what may be a helpful direction.

Best, Jonathan

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