I met one guy who insisted that it wasn't something that was needed (and preached endlessly about "radical honesty") until he got to know someone better. This was taken to the point of lying on his dating profiles, saying he was "single" when in fact he was legally married to his primary. No mention in his profiles about having anybody.
When I asked him when he brought it up, it was usually after the first few dates (which could easily have included sex). His logic was that he felt that if he hid that, it would allow the person to get to know him first, and then would be more likely to stick around after knowing the truth than if he came out with it first.
I wasn't impressed.... I think I actually called him a hypocrite to his face. He was unfazed....
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