Reading your first post I think that you might be crushing debate before it starts, save for some very loud outspoken people that may wander by. The first post is long and filled with words like "disgusting" and "dysfunctional". If I was someone who was perhaps less sure of my opinions, I might feel too afraid to post lest I expose myself to being flamed. I'm sure you're not that kind of person, Omie- I only mean to tell you that your post is pretty aggressive if you're looking for balanced debate. Now, my opinion.
Open relationships are NOT for everyone. They're NOT for just
anyone either. I can see an open relationship working between two people who are very strongly bonded emotionally, and that can respect and trust eachother's wishes. I've discussed this at length before, and what I came down to was a pretty loose and basic set of guidelines:
1. If your partner (wife, gf, bf, etc) says it's not cool, it isn't cool.
If your partner feels strongly enough to deny you when you've agreed to take a step in this direction, then you need to respect that. As I said, this sort of a relationship relies very, very heavily on trust. If you can't uphold that, you can't handle an open relationship and furthermore, your partner should probably be seeking 'true' love elsewhere.
2. Your partner needs to know this person.
You brought your significant other home to meet your mom and dad. So if you're married to them, or close, then you need to bring extra-marital (etc) partners home to meet your significant other. Open relationship means you can have more than one partner. It does NOT mean you need to just start grinding up on every floozy you run across. If your other can't know about this person, you don't need to be sleeping with them. An additional point on this:
3. Get the paperwork.
If you're going to sleep around with permission, your secondary partners need to be aware of the situation- no need to break someone else's heart because you can't tell them you're taken. Once you've gotten that discussed, the next step is to get some paperwork- recent paperwork- showing that your new partner has been tested. This needs to be shown to your other. Probably around about the same time you're dealing with step two if you can arrange it. Even if this new partner is 100% clean, though: CONDOM. Sex is one thing. Making a baby with someone else is -not- okay. At all.
There are several reasons for entering into an open relationship. Maybe it's a fetish. Some people are very aroused not just by the idea of having different partners, but multiple partners. Obviously one person can't be three persons, so at some point an additional party or several enters the equation.
Maybe sex just can't work between two given people- John Doe is permanently equipped with a catheter and is unable to function in that area, but his wife has needs. While she loves him very much, he respects that she needs to be pleased in a way he can't provide. (I'm aware there are other methods of people-pleasing.) So, trusting her, he allows an open relationship.
If you think long enough, you can find plenty of why- but you have to be a little more open-minded than usual, and account for some extra factors. A single partner relationship is the norm, and it works for most. But people aren't normal. People are odd and twisted creatures, the sum of all of the great and terrible things that life can drop on someone. Sometimes, normal just doesn't fit.
This is just off the top of my head, right now, and I'm sure there are other points I'm missing- so bring them up. As long as this forum can discuss the topic civilly, then I can represent the "for" side of things. : )
PS: Great topic idea! This ought to be plenty interesting.