I’m skeptical of this “percentage of variance explained” expression. In this setting, the only candate for explanation is causal explanation. But as far as I understand one cannot infer causation from statistical data (and heritability seems to be a purely statistical measure) without any additional counterfactual information.
Heritability is an explanation. It’s R-squared. As useful as “percent of variance explained” can be in some situations, and as useless in others.
I’m skeptical of this “percentage of variance explained” expression. In this setting, the only candate for explanation is causal explanation. But as far as I understand one cannot infer causation from statistical data (and heritability seems to be a purely statistical measure) without any additional counterfactual information.