I could never do this kind of job; it would be directly supporting a belief system that is the common one behind marriage today: marriage is merely a mutual services contract.
That aside, I don’t think I would have the qualifications either....:)
I think that, in most cases, they’re probably not dealing with married couples. The Relationship Terminator (a German man, iirc, with a Europe-wide practice) kept busy just sorting out non-marital breakups.
So the investigators in this article reflect the bizarre transference of marital expectations into shack-up relationships. I like to say that there’s no such thing as “cheating” if you’re not married: there’s just “moving on to a better deal.”