I agree with the Poly by choosing/accident/no other way around it - that's how I identify. Even though I had experience being a tertiary member of another, larger group (think moon orbiting distant planet), all that did as we figured our way into a more physical relationship with my men was inform me of the things that had not worked for me in the past.
So, yeah, I doubt very much that I would be poly/seek out poly in any other situation. I know T wouldn't and that's something he's made very clear. E might, but it's hard to say.