If we were to place the Qur'an and the New Testament side by side, it would be fair to say that the Qur'an has many more contentious issues. The form of the Quran itself makes this apparent - we have a recording of various speeches (as some have speculated to be oral lore) which are void of context. This context is filled in by the early hadith writings; that is - a number of writings produced hundreds of years after the death of Muhammad. So, as we would expect, the traditions are filled with legends - the Muhammad of the Qur'an is a mythic hero. He is a man who had the guts to lead armies against all odds; whilst he was the ultimate lover - taking in excess of 10 wives (and in addition concubines) and being able to satisfy them in a single night.
So, on what basis should one take such accounts of the compilation of the Quran as accurate -especially when the earliest Sunni and Shia accounts are mutually exclusive. If, however, we bring the criteria or embarrassment into the issue - we can paint an interesting story about the Quran. Although today Muslim apologists continually propagate that Muhammad went over the Quran one last time with Jibreel; which was later collected together after his death the true testimony of the early Sunni literature is so much more interesting.
What we have are shambles. We have men physically fighting over Quranic variants; we have variant versions of the Quran. For example, Ibn Massud's Quran had three less Surahs than that of Uthman's version (which became the official version in some sense), many verses were missing, the surahs were of different lengths and the order of the surahs was different. This in itself contradicts the apologetic approach to the sources and we can confirm it with our Quran manuscripts. If we take many of the fragments from the Sana'a find, we find the palimpsets to match Ibn Massuds variant readings in many occasions, furthermore, we find the surahs to be ordered very differently to today's version. When we turn to the version of Ibn Ubayy, we find that he had two extra surahs (chapters/books) of the Quran that were not found in Ibn Massud or Uthman's version.
In fact, we have no evidence of a Quran existing in the time of Muhammad. Our earliest evidence of the Quran occasionally backs up the state of affairs we find in the hadith literature. This is how I see it. In the beginning, we had an Arab (or Aramaic community depending on the credence we lend to Luxenberg?). This community was acquainted with the Jewish and Christian scriptures in some way - although it need not be literary, we could establish an oral source. When we find a story in the Quran it appears as one would recite a story that someone already knows. In fact, it is a story with a polemical agenda - to fix the image of the story we already have. You know of Abraham - but did you know that Ishmael was also a son of promise, etc? From here, who could we speculate Muhammad was? Was he a pious Arab god-fearer intent on harmonising the message of Christianity with the contemporary understanding of Judaism? Was he influenced by Christianity, rejecting the divinity of Christ in light of Jewish polemics? (This may very well be evidenced to by his complete lack of understanding of the incarnation and the Trinity - that is, seeing Jesus as the man-god offspring of the deified Mary and deified Father God.)
In my opinion, the above explanations may best explain how parts of the Quran first came into being. We have the poetic verses of the Quran, exalting God which many have pointed to as being of Aramaic Christian origin. However, we then have verses of convenience - Muhammad wants something done and he receives divine consent. Now, back to the incoherent narrative. When we look at the narratives of the Quran - they can be linked back to earlier apocryphal traditions. We have the stories of Jesus as found in the Arabic infancy gospel finding their way into the Quran. With this in mind, I believe it makes much more sense that the speaker was orally communicating traditions received to a group of pious followers with the intention of correcting the 'errors' they believed to be associated with these traditions. Jesus was no longer divine - but still virgin born, etc. Evidently, with the death of Muhammad his followers needed to elevate their message to that of the 'people of the book'. They, evidently, needed to become a people of the book. Of course, the irony of using the name Quran identifies the message as a recitation and not a book, but I guess they were too used to the name?
In establishing the book arose the Quran - a compilation of oral lore embodying the religious and military aims of the group.
In light of these ramblings, I should write a book on the origins of Islam.
To be continued one day...with references.