Shalizi’s usage seems perfectly reasonable to me. People use the phrase “highly heritable” to refer to the experiments they actually do, not to the theoretically best experiments they could do. Shalizi claims that performing the same experiments with accent would yield a conclusion of “heritable.” (though he backs off of “highly” and is generally evasive about quantity)
Shalizi’s usage seems perfectly reasonable to me. People use the phrase “highly heritable” to refer to the experiments they actually do, not to the theoretically best experiments they could do. Shalizi claims that performing the same experiments with accent would yield a conclusion of “heritable.” (though he backs off of “highly” and is generally evasive about quantity)