While Regnerus critiques "same-sex couples" raising kids, his study does not actually compare children raised by same-sex couples with those raised by different-sex couples. The criterion it uses is whether a parent "ever ha[d] a romantic relationship with someone of the same sex." In fact, only a small proportion of its sample spent more than a few years living in a household headed by a same-sex couple. Indeed, the study acknowledges that what it's really comparing with heterosexual families is not families headed by a same-sex couple but households in which parents broke up. "A failed heterosexual union," Regnerus writes in the study, "is clearly the modal method" — the most common characteristic for the group that he lumps in with same-sex-headed households. For example, most of the respondents who said their mothers had a lesbian relationship also endured the searing experience of having their mothers leave the household as the family collapsed.
In other words, Regnerus is concluding that when families endure a shattering separation, it is likely to shatter the lives of those in them. And this is news?