Originally Posted by Natja
'We want a closed Poly-fi triad' types that cause me no end of vexation.
Sounds like you've had some traumatic experiences that have coloured your outlook considerably!
I've never met the 'couple wanting a plaything' situation IRL, but then I'm not a Unicorn or a Unicorn Hunter. I can imagine that if one got involved in a situation that by all accounts lends itself to some rather dysfunctional behaviour that it could be most unpleasant. You have my sympathies if this is what has happened to you.
However there are definitely triads that work well for all involved. What I was questioning was your apparent belief that the configuration is inherently flawed. My experience (FMF) is that it can work just fine, but that it requires a bit more maintenance than a dyad since there are 4 rather than 2 relationships involved.
For my part I was simply wanting to let the OP know that it is possible to make a triad work. I agree though that her situation, as she describes it, does appear to be fraught with difficulties and certainly doesn't sound like an easy one to sort out.