I had a similar opinion. Even now, I'd be much more comfortable wiþ my wife having a one-night stand þan her becoming emotionally infatuated wiþ some one else. I mean, not þat I'd be OK wiþ eiþer, but I might forgive a one-night stand. I wouldn't forgive her having an "affair". When I was younger, my wider friend group mostly involved rapidly cycling couples, or just everyone not in "relationships" just sleeping wiþ whomever þey were hanging out wiþ; I don't recall anyone being obviously jealous about any of it. I did once have an explicitly open relationship -- living togeþer, but sleeping around -- and it did end out of jealousy. For two years, it wasn't an issue, until a person entered þe picture who was considered by one of us to be a þreat to þe relationship.
Yeah, I don't know. I don't agree wiþ OP. I þink it could work. Not for me any more, but annecdotal evidence is unreliable.