it feels like the discussion is falling into a binary trap and losing the ability to look at multiple solutions. What are all the possible acceptable outcomes?
we all had to work at throwing out underlying preconceived notions and look for creative solutions that weren't necessarily shaped for either end of the kitchen table vs parallel pigeonholes
An interesting question, but doesn't do much to advance the discussion. Like, it's not "a binary trap" if there's a choice between two paths; people who speak only of the two paths -- rather than some yet undiscovered alternate route -- aren't somehow faulty or unenlightened.
Tell us about those other paths, rather than stop at "what if" as though it's someone else's responsibility to dig deeper.
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Personally, I think the whole concept might be a pile of false dichotomy, possibly imposed by the people involved having no experience with nonmonogamy beyond "marriage + 1."
When our intimate network was flourishing, there were some who simply had no interest in the "one big happy family" stuff. Even those of us more the "kitchen-table type" balked at feeling
obligated (to participate or to include others, possibly reluctant) or that it had to be going on all the damn time.

Someone might like to hang out for our planning sessions but not be particularly interested in the parties, or join discussion get-togethers but not tag along for mall shopping. If I didn't feel like attending brunch or whatever, it wasn't as though I'd somehow "changed my mind" about hanging out with a group.
Life is often more
à la carte than
table d'hôte.

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(I'm still uncertain how two lines radiating from the same point can possibly be parallel...

)
Since the term "hierarchal" is often so poorly defined, its use should cease, particularly when it's held up as somehow evil. (There is nothing inherently "hierarchal" about "parallel" relating.)
There is nothing "non-hierarchal" about "established couple, plus 1." It's a
slip that likely says much about the actual relationship dynamic.
The wife (let's call her Wilma) might be interested in polyamory as an ideal, but is finding it problematic to make real. It seems inconsiderate (at best) that anyone would be trying to weasel her into hurrying her "evolution" for THEIR convenience.
It's quite possible that when Wilma begins to show interest in dating, the husband (call him Harry) will totally lose his shit & try to impose all sorts of restrictions on Wilma, maybe even pushing to go back to "the good ol' days" of the present vee.
If Wilma wants to "save her marriage," she's at least got her terminology wrong.
The old marriage is over, period. If Wilma wants everything to stay the same, including time that Harry has to spend with her & do stuff around the house, yet have a secondary relationship, then she's deluded.
Harry certainly wants the "kitchen table" stuff, likely because he's still harboring harem-building notions & taking his role as hinge to be more a "king of the house" thing. He wouldn't like it so much when he starts getting vetoed by the women working together.
