Utah SSM Court Decision a Bad One (Constitutionally Speaking)

I've read the Amendment 3 court decision (striking down Utah's law defining marriage as between man and woman). After reading the decision (PDF), I find that the court's conclusion is based on bad logic and an incomplete survey of history.

It's a badly decided case.

Without a better argument than this case, I will continue to state: nothing in the US Constitution requires Utah to permit any other kind of marriage than one man, one woman. I've studied that Constitution pretty closely, and I understand the reasoning that is applied by the pro-same-sex marriage lawyers; I just don't think it holds together.