Outstanding article. Shoemaker is one of the few contemporary scholars (along with Gabriel Said Reynolds and Guillaume Dye) who I tend to agree with on almost everything --- I think he nails it over and over again, while many other scholars have lots of interesting insights but tend to fall short on the overall picture.
It's really incredible how often the basic, manifest meaning of the Qur'an is overlooked by both Muslims and modern scholars in favor of tendentious broader narratives. The traditional narratives about Mohammed as social reformer all hinge upon the concept of a pagan polytheistic jahiliyyah, where everybody was ignorant of monotheism and civilization, and Mohammed received revelations about behaving decently. But this is nonsense; it has been demonstrated over and over again that the Qur'an reflects a literate environment already suffused with Judaism and Christian traditions. There were almost no actual pagans, and certainly everybody had heard about Judaism and Christianity. So what reforms did Mohammed allegedly introduce? And why aren't those reforms present in the Qur'an, which is notoriously lacking in such specific guidance (hence the need for Muslims to create the hadith and Sunnah, because the Qur'an itself has so little legal/social guidance)? And how could these possibly have been considered 'reforms' in an environment that was already chock full of Jews and (albeit to a lesser extent) orthodox Christians?
To answer these questions, scholars have traditionally resorted to elaborate historical fictions about the Jahiliyyah and its practices in the mid 7th century, fictions that have never withstood any kind of critical and historical analysis.
Many people claim that Mohammed ripped off the Jews with his social reforms, but this is false -- the reality is that the Qur'an reflects an environment in which the culture was already dominated by Judeo-Christian and general Near-Eastern practices. There was nothing to reform. The Qur'an's message is not a radical innovation and (it is sad this has to be repeated) it explicitly claims to be a reminder and a warning of the same message previously given to all the Judeo-Christian prophets. Far from 'reform,' it is a call to REMEMBER and HEED the eternal divine message, to be pious, to think about judgment day and the bodily resurrection.