Twin tests have proven that, one identical twin is adopted by a wealthy family and goes to a top school. While the other is adopted by a poor family and goes to a shitty school. Later when they get tested
I'm totally aware of the twin tests and I don't disagree with it.
In fact if my argument has a week link that's it.
I think there's something about genetics we don't fully understand or acknowledge.
Let's take your example of mayweather or crazy horse. If they were to grow up with excellent education would they be brainsurgons. Probably not likely. What about if their kids and grandchildren receive excellent education and their parents are of equal IQ /ethnicity. I think they definitely would be capable of that and those kids would be Ben Carson level smart.
I don't think anyone can adapt to any environment. But I do believe they can within a few generations totally independent of race.
( slight tangent ) I don't think the earth is flat and the moon is it's own light source but there is clearly something about the photon that scientists do not understand and worse yet , don't even acknowledge they don't understand it.
I see this area of IQ the same way.
To put it another way. Do we really have to do a study to know the results of , if you take a random community of blacks with low IQ scores and give them high level education and not a poor environment are their IQs going to be much , much higher in 3 generation's? Of course they are , they would be comparable to any other high IQ race if not higher.
Also , to your first point , all of the data people rely on for the ethnic comparisons of IQ are based on high school scores. So that is the basis of what we're talking about. The other tests are also a much more of an indication of education than IQ. Worse than that they can be studied for , which makes the value of them worth fuck all.