Well, look at mormanism. A certain side of mormanism advocates polygamy. But that is still illegal. What makes you think that the government would then allow same sex marriage because a religion says it's okay? A nice ideal, but unlikely.
Marriage isn't the bad part. It's the people entering into it. People think that allowing same sex marriage perverts what marriage is supposed to be. But us straights are the ones who have already done it. People don't seem to realize that marriage is work. They enter into it all dreamy eyed not paying attention to harsh realities. You will fight, you will dislike eachother (possibly even hate at some points), and you will wish you had never done it. The hope is that the good times far outweight the bad. People just expect perfect and get out at the first sign of trouble. We should not be excluding people from a ritual that we can't even seem to get right.
I'm in no way stating that I am against same sex marriage. Quite the opposite. I'm just saying that I think your plan doesn't have a shot. You think that gay marriage rights can't be abused? Humans will think of a way to abuse everything.
Isnt there discrimination between different types of straight marriage though. A straight couple thats married with kids, from what I've seen they often dont view the marriage of a straight couple with no kids in the same light, the same sacrifices are simply not made. similar with a straight married couple that are arduously monogamous, they dont view those in an open marriage in the same light
Religeon and non-hertosexual will never work, religeon is designed to make you think differnty to how you would usally.
Oh I actually think that this has some validity as well as is possible. Religion is a common belief system, nothing more. There are some pretty widely shared beliefs among homosexuals. If it was more organized I would not be surprised if it worked if people got on board with it, which is where I see downfalls. I dont know many people who would switch or tag on religion to get marriage. If people want religion they have one, and if they dont they more than likely would not be looking for one. But cool idea let me know if you actually do something with it.
