I don't get what you're saying about "genetic propagation" -- we aren't talking about a previously nonexistent gene spreading to every individual, just a change

I don't get what you're saying about "genetic propagation" -- we aren't talking about a previously nonexistent gene spreading to every individual, just a change in the statistical distribution of genes. All that requires is for certain kinds of people to have babies faster than others. In any event, I appreciate your taking the time to substantiate your claims. Doing so helps keep the quality of discussion here high.