Lee Faber has two pertaining to the insertion of Scotus into a genealogical narrative and using of sources (or the lack of proper sources): MacIntyre on Scotus and Alexander Broadie's Gifford Lecture
One should attempt to understand the arguments of a medieval on their own terms instead of relying on secondary sources in intellectual history or even philosophy, making use of followers of that tradition and contemporary scholars. This should not be so hard to understand. Even though I can respect MacIntyre for the philosophical and rhetorical value of some of his arguments pertaining to moral philosophy, it is unfortunate that much of his work is tied to intellectual history. (Alas this is because of his theses concerning moral epistemology and tradition.)
Better to understand one tradition well and argue accordingly -- leave the understanding of history to the Beatific Vision.