I think whether this 'friends' thing works or not depends largely on how much trust you have left with your spouse.
I've seen it work with a couple I'm close to... but there was no infidelity involved. Just remained friends as they've known each other for so long, at times hanging out together. At one time H was in a very short R with someone else. Their friendship grew intimate again and they got back together a year later.
They didn't know anything about DB, so it's not that they applied any 'techniques'.
My H asked to remain friends as well but it makes me a bit sick... he was verbally abusive and 'friends' sounded like it is to serve his purpose of being let off the guilt. So much easier to detach when you're not friends anyway.
