Why the focus on Lynn?

Focusing on his critics is more illuminating and damaging to your presumed position:

Systematic review by Wicherts et al: "In light of all the available IQ data of over 37,000 African testtakers, only the use of unsystematic methods to exclude the vast majority of data could result in a mean IQ close to 70. On the basis of sound methods, the average IQ remains close to 80."

They of course follow it with the conjecture: "Although this mean IQ is clearly lower than 100, we view it as unsurprising in light of the potential of the Flynn effect in Africa (Wicherts, Borsboom, & Dolan, 2010) and common psychometric problems associated with the use of western IQ tests among Africans."

It's always curious how "common psychometric problems associated with the use of western IQ tests among Africans" don't carry over to economics and other things. Wouldn't you expect them to have similar problems with other western "ideas"? Also interesting how Easterners adapted to western IQ tests so well they are better at them than the West.

Part of the point of the Wicherts papers was to refute the Lynn data, observing that even taken on its own premises Lynn's team pretty clearly excluded data unfavorable to the conclusion they wanted to draw. But look at Wicherts 2009, at the samples they're talking about. One of the largest was 800 students in Nigerian high schools (a test arranged by IQ researchers to for a cross-cultural comparison, back in 1981). Lynn's data includes, and is materially influenced by, a sample of 59 Senagalese children who were tested while recovering from malaria. The malaria thing is just funny, but it's the numbers that stick out to me.

I'm not getting further into the details here because the easiest-to-understand point here is that there are not in fact programs to generate reliable "average IQ" numbers in different countries. I am struck by the fact that message board nerds from America believe these programs exist, when almost none of us have ever taken an IQ test.