I'm glad you're here posting, Choc/Pup! You give a lot of consideration and support to people in need and it's appreciated.
I may not agree with you all the time, but it's good to have the option of hearing a point of view that's different from my own. As things have played out in my own sitch, I may have done better in adhering closer to your advice, but it's hard to choose the right path when you're in the midst of emotional upheaval.
Infidelity is the one area where DBing is a little shaky. We definitely can improve ourselves and we benefit by employing DB techniques in our own lives. But our spouses HAVE to be remorseful if anything can be resolved and they have to end the affair.