I don't think the outside view is relevant here. We have coming up on a century of twin studies and behavioral genetics and very motivated people coming up with possibilities for problems, and so far the traditional estimates are looking pretty good: for example, when people go and look at genetics directly, the estimates for simple additive heritability look very similar to the traditional estimates. The other day offered an example of a SNP study confirming the estimates from twin studies, "Substantial SNP-based heritability estimates for working memory performance", Vogler et al 2014. If all these complexities were real and serious problems and the Outside View advises us to be skeptical, why do we keep finding the SNP/GCTA estimates look exactly like we would have predicted?