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No idea. Factor analysis is the standard tool to see that some instrument (fancy work for ability) is not unitary. It's worth learning about anyways, if it's not in your toolbox.
It is already in my toolbox, but I'm not sure how it helps figure out if this phenomenon is present in the real world. It's still not obvious to me that, if the phenomenon does exist, it would survive when reduced to a unitary ability. I can think of a couple of mechanisms by which it may be more prevalent in a multivariable scenario.