Regardless, the mere existence of a fashionable trend does not mean that Johnson is a practitioner of it.
I'm all for Catholics being honest about evil actions by Catholics in the past. Johnson simply was not accurate. Madden's work is excellent and Jonathan Riley-Smith and a host of other crusade historians have all made many of the same points. That's where the thread started, with Madden's work, which is excellent. Read it. Forget Johnson's book. It's simply not helpful; I can't imagine that even Johnson would defend it today, but perhaps I'm wrong.