Wansbroughs entire analysis was based on the assumption that the canonization of the Quranic text and its role in the development of the Muslim community followed a trajectory similar to that of Hebrew scripture.
For example, in connection with exegetical (Wansbroughs characterization of much of the content of the Sirah of Ibn Ishaq, ca. ۸۵-۱۵۰ / ۷۰۴-۶۷, edited by Ibn Hisham, d. ۲۱۸ / ۸۳۳) reports of material that also appears in the canon, he declared: For Hebrew scripture the priority in time of such reports over the actual reproduction in literary form of prophetical utterances has been established.
To postulate a similar, if not identical, process for Muslim scripture seems to me not unjustified, though in this particular instance complicated by the redaction history of the Sira itself. He also cited the likelihood of a Rabbinic model for the account of an authoritative text produced in committee, namely the Jamnia tradition on the canonization of Hebrew scripture.
The vastly different historical contexts in which these supposedly parallel processes took place were not explicitly recognized or taken into account in Wansbroughs literary analysis. In fact the results of this analysis were frequently cited as grounds for rejecting the supposed historical evidence presented in such texts as the Sirah.