Inspection Time, IQ and Flynn

Inspection Time (IT) is when the testee is asked to do a very simple task. Usually they keep their finger on a button, surrounded by other buttons with lights above them. One of the lights lights up, and their job is to press the button under the light to deactivate it.

The Flynn effect is the rise in IQ scores over the last few decades within age groups (cross-sectional, not longitudinal). Im no expert on the Flynn effect, and the experts are of course divided - how much of this is genuine disagreement and how much is the usual liberal fudging and setting of impossible standards for non-environmental viewpoints, I dont know.

Recently it was reported that the Flynn effect seems to have reached its zenith in modern Industrialized countries. But IT scores are pretty stable

The thing is IQ and Inspection Time are inversely correlated. The faster you press that lil button, the higher your IQ tends to be. The correlation is about -.40

So, we could reasonably assume that IT tests are measuring biologically (in part at least) what IQ tests measure academically and less directly.

This makes me wonder about many of the recent IQ tests being administered, particularly on backward groups. See here for tests done on the Roma Gypsies.

Why arent they taking an IT test at the same time?
Granted, IT is supposed to be static therefore such readings can be taken later, but a little more data to buttress conclusions never hurt.

And why arent we comparing IT from groups which presumably have had the Flynn effect work on them - say Lower class American Blacks, and comparing these results to other groups where the flynn effect has not ended, indeed in some cases where it plausibly hasnt even started?