Well the swinging lifestyle only seems to work if the couple themselves are open, honest, trust one another completely and love eachother deeply.
I didn't 'get it' for a long time. But my friends are crazy in love, they just have evolved sexual parametres? BUT it's not just about smashing other people....it's making the decision together always.
I remember them telling me once about a middle aged couple they hooked up with, apparently the man (older guy) had a penis on the small-ish side and his wife was in pretty good nick for an older bird. My friends hubby was going to town on the wife and she was screaming like a banshee having multiple orgasms and the hubby went BESERK apparently. He just couldn't handle his wife having such pleasurable sex, in the same room, with another man.
My friends stopped and left and later heard from the wife, who said hubby had agreed to swing because he wasn't able to satisfy her sexually anymore.
So you see? If you're swinging because your hubby wants to, or your wife wants to and you're doing it for them it aint ever going to work.
Same can be said for a threesome!
You have to do it, because you want to do it, because it turns you on and because, as a couple, you've agreed that you will do it together.
The end.