1. Didn't say 'restraint'. Social scientists say it is a constraint, you prove it's not.<quoted text>
Prove that the primary purpose of marriage is, and has always been, to restrain people's mating behaviors.
Prove that it is and always has been successful in doing that.
Then prove that gay folks marrying will cause straight people to mate with even less restraint.
2. No one said it had to be successful
3. There is no such thing as gay 'marriage'. The only result of saying there is, would be the redefinition of the word. Meaning that ss couples would still not really be married in the true sense of the word.