That’s “a” logical way to explain it, as we’ve explained before.
But it doesn’t explain the NDDs complete lack of any actual evidence showing it, as we’ve ALSO explained before.
And for all the work done on “Blacks”, it still doesn’t explain NDDs position of “Orientals” who are more intelligent than “whites” and “blacks” in his ssytem. They are apparently the intelligent subset of “Mongoloids”, which is the less intelligent grouping of all Asians. I’m not kidding about that, check his posts. His explanation of evolutionary “pressures” in “Orientals” is the Chinese Imperial Exam system, which has been in sporadic existence for only 2000 years.
A good portion of the opposition comes from the fact that NDD just doesn’t know what genetic evidence is, doesn’t understand how to control for socioeconomic factors, doesn’t understand the difference between genetic and biological factors, and doesn’t really understand the notion of a falsifiable position.
Basically, much of the opposition comes from the fact that NDD doesn’t actually get basic science, even at a high school level.
And, of course, that completely ignores the NDDs rather bizarre claims, such as an average IQ of 58 for the San as a group, the rather bizarre claims about the Japanese, ignoring test results from within the US itself for Hawaii (East Asians, this time, rather than blacks). His position also explicitly suggests that he doesn’t understand the concept of a mean, as small groups of educated Africans (Nigerian graduate students in the US, for example) are apparently impossibilities. Oh, and there was also the related bit about how President Obama obviously got his intelligence from his mother’s (white) side of the family, despite the fact that his father also went on to do PhD work.
You can try to defend a “version” of NDDs thesis all you want. But your particular defense simply pokes more holes into NDDs existing thesis, which never made any sense to begin with.