The conversation seems to turn on whether marriage has a causal effect on other values relating to success. As Glenn points out, just getting married doesn't change one's priors, so the effect it has on the couple in isolation may be limited (though probably non-zero). But perhaps the pro-marriage argument (made in isolation from school values, delayed gratification, etc) is that the big effect it has is on the couple's child, and less so on the actual couple.
Assuming the couple actually stays married there will like be more stability, more # words/day the child hears, higher earning potential of the overall family, higher education standards, and lower crime rate; all of these things give the child tools that *do* cause success. This is basically the crux of Obama's fatherhood speech: https://www.politico.com/story/2008/06/text-of-obamas-fatherhood-speech-011094. That's at least the more defensible claim here (and would need the proper research)
The conversation seems to turn on whether marriage has a causal effect on other values relating to success. As Glenn points out, just getting married doesn't change one's priors, so the effect it has on the couple in isolation may be limited (though probably non-zero). But perhaps the pro-marriage argument (made in isolation from school values, delayed gratification, etc) is that the big effect it has is on the couple's child, and less so on the actual couple.
Assuming the couple actually stays married there will like be more stability, more # words/day the child hears, higher earning potential of the overall family, higher education standards, and lower crime rate; all of these things give the child tools that *do* cause success. This is basically the crux of Obama's fatherhood speech: https://www.politico.com/story/2008/06/text-of-obamas-fatherhood-speech-011094. That's at least the more defensible claim here (and would need the proper research)