This depends on just how specific a skill is, whether or not the particular subject is a polymath or specialist, and much more.
To take an example from athletics, Lance Armstrong was a world-leading cyclist (with, it turns out, the advantage of doping). When he entered into marathon events -- for which his light body frame is generally still an advantage -- he placed respectably, but not as one of the very top finishers. A skills or abilities test for Armstrong had to be specific to his ~60 km cycling distance specialisation.
There is some crossover of many skills, but the deep specialisation, ingrained structures, algorithmic knowledge, solution sapces, bags-of-tricks, etc., that are associated with being best in class (not merely "very good") can be quite complex.