I have some questions concerning Hoyland´s and also Shoemaker´s arguments:
1/ Has the discussion been concluded amongst mainstream scholars about the location where Quran originated ? The (non)presence of Christians-Jews in the Hijaz becomes non-essential in the discussion if Quran originated in North-Arabia (Syria) and not in Hijaz. But neither Hoyland nor Shoemaker seem to have any doubts on this and focus their arguments how stories-texts of Jewish/Christian nature could have come to the Hijaz. (Could the question not be here: did the Quran go to the J-Chr sources or did the J-Chr sources go to the Quran...)
2/ Hoyland stresses the parallelism of the Christian stories and the Quran. He uses example 19:24 (about baby Jesus sending a rivulet under Mary). This happens to be an example Gallez highlights as being proof of Syrian-Aramean influence on the Quran since even in the DIB- Turkish official Quran this verse is translated as "your lord has made your child legitimate ([own translation from French
..[/s][http://www.lemessieetsonprophete.com/annexes/Luxenberg_s19-24_turc.htm./s]
Assuming pre-knowledge of the audience must have been, just as it is today, a tricky business. I think all teachers can confirm this... Thus, using pre-knowledge of the audience to explain a "weird" text seems to be a too easy way out.
3/ How similar were Hebrew/Aramaic-Syriac/Arabic to each other? Cant it be that Arabic christians didnt feel the need in 6-7C to have their own Arabic translation of the bible because of the similarity of their language with Aramaic-Syriac? Just as Plat-Deutsch speakers accepted the Hoch-Deutsch Bible a millenium later? Only after Arabic gained the prestige it did later on, was the need felt to have an Arabic translation? Explaining the later indications of the existence of an Arabic Peshitta (post- Quran)?