I'm going to take a different approach. You see, right now I am with two men, neither of which are with others. Yes, it works for me, however, it's not what I demand.
I accept that should/when either of them dates or meets someone there will be adjustments. That there will be times I am not getting the same level of attention as I am now, that I may even get jealous at times. Guess what? That's my shit to deal with.
Instead of worrying over not getting the same level of attention I choose to look at it like this. My partners are good men, are there for me when I need them. They are the kind of men I hear women constantly lament they can not find. So why wouldn't I want to share that? They find a good woman who they also love. Why would I not want someone else to know and appreciate these wonderful men?
It doesn't, it won't, lessen OUR relationship or OUR commitment to each other. It will make them happy, so honestly, the negatives I see are all things I myself need to deal with. Not them. Not limit them and their relationships.
Me: Late 30s pansexual poly.
DH: My husband of 19 yrs and father of 3 teen girls.
DC: LDR of +4 year