I think that it's a bad idea to replace one default model with another. The problem with our current mono-focused society is that monogamy is presented as THE one-size-fits-all solution to relationships, and it's so obviously not. But poly takes a lot of balancing and juggling, too, and doesn't suit everyone at all times. It's important to be able to look at the different needs of relationships through their evolution and be able to have more than one solution.
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