There are actually some courageous German academics working right now to compile a critical history of the standard text of the Koran, tracing the very process of redaction you mentioned. Fascinating, isn’t it?
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Yes it is, if it is ever published, and if they live. I remember reading about this or a similar effort a year or so ago.
The ancient Syriac, which the koran is written in, makes even native Arabic speakers scratch their heads in places.
Particularly interesting are coins which predate Mo with koranic symbols... the Saudis are doing everything they can to suppress this and other evidence that Mo may never have existed, and that Islam is a much older derivative of another religion aka Meccan lunar/rock worship.
As for the standard text, well that is the main problem, since all the originals were deliberately destroyed to prevent the very thing the Germans are attempting. They have no original sources or authors to compare. Only the Saudi authorized version exists.