I've no idea even what it means :P I assume it's something like when two people are adult and mature enough to realise when something isn't working so they make the decision to separate/part/end the relationship and they presumably do this in this way in order that it can be done as nicely as possible, sensibly and hopefully retaining friendship and respect?
If so good idea.. I approve.. I always tried to stay friends with people I met... and always ended things nicely.. If you know it's not right it's best to end it.. it only causes more hurt to hang on if you aren't feeling it..
You are right, as is LyricalOne. Some of the information that came out when Gwenyth Paltrow and Chris Martin split was that they were doing unconscious coupling. One of the themes behind it is that you choose someone who is different from you to begin with- that you like those traits because they help you grow. And, you either grow and develop the same traits or you grow tired of the traits. In any case, the breakup is on you, for choosing a partner who is different, and so you part without blame.