Does Hayes get into why separated twin studies show such high correlation between cognitive traits if not because of a strong genetic component?

And why neurodivergent people end up different in various ways despite apparently extremely similar social environments?

Also, does Hayes properly explain the complex interrelationship between genetics and environment (as one of many examples, a social experience can cause release of stress hormones, but how much depends on which alleles a person has; and circulating stress hormones are detected by (some) cells which change the expression level of (some) genes...but by how much and which is determined in part by which alleles that person has), which really makes a lot of questions like this largely a moot point? Or is she, as many people are, stuck in more of a "genetics or environment" mindset?