OK, NY, I get your point. As it happens, H loves to read, has expressed interest in these books, and in fact went out and bought "Not Just Friends" without any influence from me. He was fascinated by how well it described his situation, but didn't choose to follow up on the suggestions on how to act on the situation.
So just now I purchased the Huizenga book and am reading it for myself. It does seem consistent in most ways with the divorcebusting approach, and is focused specifically on how to deal with an affair that is going on right now.