Reading Alasdair MacIntyre's Three Rival Versions of Moral Enquiry brings home what a gargantuan task scholars of the Middle Ages undertook when they integrated Aristotle into their Augustinian curriculum.
The absurdity of the claim that thinkers in the Middle Ages slavishly followed Aristotle can be demonstrated by two simple points:
1) For most of the Middle Ages, Aristotle was essentially unknown in Western Europe. Scholars during that time hardly could have "slavishly followed" him.
2) Once his works became known, they collided, often violently, with the existing schema of the sciences. It took a huge intellectual effort, involving rejecting some parts of Aristotle, reinterpreting others, and amending yet other parts, before Aristotle could be fit into a new structure of knowledge.