Well you raise an interesting point, Jedi. What, exactly, does "Qur'an" even mean? It's well accepted by scholars that it derives from the Syriac term "Qeryana", meaning "lectionary." And what's a lectionary? In Syriac, a ktaba d'qeryana, meaning a book that one recites from. This use predated the Qur'an, and it did not simply mean 'oral recitation,' as later Muslims would attempt to interpret it. It meant an ACTUAL book that one orally recites from.
The technical use of this term, circa 630, would have meant a recitation that relates to a sacred text. It is only the much later Muslim tradition that insists on the orality of the text as *primary.*
I consider the Qur'an to be a composite text, reflecting input from many different authors, scribes, compilers, and redactors. Just like virtually every other sacred text (for example, the Gospels).
So I do not at all think there is anything complex about the Qur'an referring to itself as a "kitab." It is because at a certain stage of compilation, it was a written text, and thus properly refers to itself as such. No mystical divine books in heaven needed to be jammed into a text that doesn't say anything about that. There is a debate about whether or not the Qur'an was primarily transmitted in written form at one point, without a secure oral tradition to accompany it, and I think it (or more properly its predecessor components) unquestionably was for a variety of reasons. Here's one: The current text appears to contain certain garbled Syriac terms that were no longer properly understood by later Muslims, of which "Qur'an" is one. Great article from Donner on the Qur'anic term "Furqan," which is another.
http://www.academia.edu/1013511/Quranic_FurqanKey point: "The implication is that some passages of the Qur’an text must have been transmitted, at some point, only in written form without the benefit of a secure tradition of oral recitation, otherwise the misreading of Syriac ‘puqdana’ as ‘furqan’ couldnot have occurred."
Both these terms would later be interpreted by Muslims in a way that is inconsistent with how the Qur'an uses them, and elaborate theological and mythological explanations would be developed to try to explain that.
The point being that this was a *text*, and its recitation was derivative of its status as kitab (the real kind, a mushaf, not a heavenly magical kind). Furthermore, in the community that recitation I think was in different phases -- an early phase, consistent with Meccan surahs, and a MUCH later Muslim phase, in late Umayyad/Abassid times, where Qur'anic recitation became a dogma, concomitant with arguments about Mohammed's alleged illiteracy.
Topic: Muhammad Wasn't Illiterate