Call it what you want, and I neither agree nor disagree with it, but the whole thing of "acting as if" is "pretending". Thus the word "acting".
Sounds fine to me if he wants to say "If you want to stay married, then......". That sounds OK to me at the proper timing. Not sure Mrs OIN is far enough over OM to be giving an ultimatum right now.
And this is my opinion based on what I believe, but if I told my W she was no prize, I'm not sure that humbling would come to mind for her.
I do agree that OIN needs to think more strategically now about boundaries. Boundaries does NOT include a tit for tat.