[tptacek]

You're lost here. Heritability is defined technically as h^2 = V_a / V_p, with V_a additive genetic variance and V_p phenotypical variance. Look at your hands. The number of fingers on it are extremely genetically determined; the Hox genes that define your body plan are very conserved. V_a is practically zero. But plenty of people have fewer than 5 fingers, and some are born that way (for instance, children exposed in utero to Thalidomide); V_p is nonzero. Evaluate the expression (0/nonzero).

If you read your own words carefully, you're trying to rebut the parent commenter with their own argument.