Some excerpts reveal a mindset. His is a secular humanist drivel, adequate in discussing the events of the 19 century, completely useless in comprehending the Middle Ages. In addition, the tone of the excerpts is unprofessionally propagandistic, as he goes from one anti-Catholic button to the next.
My understanding is that he is, in fact, a practicing Roman Catholic. Perhaps his response to your criticism would be that a realistic appraisal of past Catholic error is not "anti-Catholic" at all.