They're two very different approaches, as you've seen. While I think you can pick up bits and pieces from each, I do think that you have to decide pretty much which fork in the affair-busting road you're going to take, since they ARE so different. It's only going to confuse you if you keep going back and forth.
I have a ton of respect for the Harleys, and their teachings -- they, along with MWD and a few others -- helped save my marriage. Their forum and some of its leaders . . . ehhh, not so much. LOL