BIG QUESTION: Would you support polygamy as a hedge against rising divorce rates?

Is it fair to say that divorce rates are lower in polygamous societies? Might it make sense now that we are re-doing our definition of marriage to legalize not only gay marriage but also polygamous marriages? Arguably, by doing so, the divorce rates will cut in half in this country, adultery will be significantly reduced and people will be happier in the institution. Doesn’t that make sense? When you consider the fact that adultery is at the root of so many divorces in this country. Look at Elin and Tiger who announced their divorce recently. This is not funny. But I’m thinking that if polygamy was legal, we could avoid meltdowns like this.
I mean, what is so special about the two-member marriage? Why can’t we have three or four people married at the same time? Is it the procreation argument? Because, obviously, that is pass√©.