The legal ramifications are the same as well: Property rights under the union, taxation, child guardianship, visitation, protection upon dissolution, and wills.
So the child of a divorce has to move between more than 2 homes now? A wealthy man can split his income with more than 1 wife that doesn't work?
It's not the same, it's qualitatively and quantitatively different. Is there a limit to the number of members? Can you join a union halfway through? Can you leave a union without dissolving it? Those questions don't come up under 2-person unions.
I'm not sure why you keep harping on the specifics of the rules. Any different arrangement will always have different specifics, even if the fundamentals remain the same (which they do in this case).
What is the difference between specifics and fundamentals? Aren't the legal ramifications the fundamentals? I mean, it is a legal institution that we are talking about, right?
I'm not saying you can't have a loving and intimate relationship between 3 or more people, I'm just saying same-sex marriage is much closer to heterosexual marriage in terms of legal ramifications because it's only 2 people. Lines and triangles are both geometric figures, but that doesn't make them fundamentally the same.
You said the difference is academic. No, it requires significant changes to the legal framework of marriage.
Consider the following programs:
1) A program that allows a PC to talk to a Mac
2) A program that allows a PC to talk to a PC.
3) A program that allows a Mac to talk to a Mac.
4) A program that allows any number of Macs and PCs to talk to each other all at once.
The point is that given 1, it's pretty straightforward to write 2 and 3. 4 is a just a lot harder to get right. I'm not saying it can't be done, but the difference in the patches required to support 2, 3, and 4 is not academic.
Laws are pretty similar to programs, and there's a big jump in complexity going from 2 of something to 3 of something. Anyone that was actually poly would know this from all the honesty, negotiation, and ground rules that are required to make it work.
