I, for one, relate to the confusion between poly and open. I went from a relationship which was primarily poly-fi, and there were FWB, but they were emotionally very separate, to a poly relationship where my partner is very open as well as poly. In my old relationship we were a triad, and any play on the side was solely that, play. There were no deep emotions involved. The partner I have now is very different. His FWB are very close and dear to his heart. This blurs the line between open and poly for me. It is hard even for him to put a definition on what makes our relationship different from his other ones. It has shown me that the line between poly and open is not as clear cut as I once thought.
It also has been a cause of struggle for me. There is a sense of security in the black and white separation. I can see now that poly is so much more multi dimensional than I even thought! So, while some of us may feel talking about the issues with "swinging" and being "open" may not be polyamourous issue per se, (and there was I time I would have been insulted to see those things linked together) I see many poly folks do not like to draw lines (separation walls) between their committed poly primary partners, their secondary partners, their FWB, their non sexual loves, their one night stands... because there may be no limitations (per their individual agreements) to where any of those relationships could develop, or are developing to.
So, even though I am a strong believer in poly as dealing with the emotional aspects of loving multiple people, who is to say my definition is the only one? And many people find it hard to separate love and sex, or even emotional involvement and sex. Are the discussions here becoming more about sex and lass about relationships? Maybe, but I also think the group as a whole is opening even more to all the shades of grey between poly-fi and true swingers.
Hopefully, I didn't stray too far from topic...