I see where you are going with what you wrote. And it makes sense. But, in my situation I don't know how you would define it. Mine and my husbands relationship started out mon. But over the four that we've been together we decided to change it, we want to add to it. So though our relationship changed we did not. We are the same people, same beliefs we always had. We just didn't realize until we were together that this is something that we would want. It's strange how it all came about, it's even stranger that though we both thought it for a while, neither of us would say it out loud. We were to worried about losing each other, which we never want to happen....and it's never going to!!
So I do have to disagree. It's hardwired into us, that's for sure. It was there all along, but we chose this. Our relationship started mon. and has ended up poly.
But I like what you wrote!!