Testing: does individual skills matter?

[Toxcatl]

don't research too much
then all gonna lost you like AI

We must know, we will know. Or die trying =]

About tests. It goes very slowly, because I can't play more than one friendy each day against the same opponent, and I need to have the same starting conditions for every game. I wanted to do several tests with different orders and bonuses, but with current speed of testing the idea with bonuses best to be left forgotten.
I'm doing it with Zonal and Low pressing. I don't see any correlations between Fitness, AvgPM, Quality and CL. Maybe with High Pressing and Man-2-man there will be difference, but I tend to think that either nothing reduce CL (and high Fitness just negate invisible condition penalty or something like this) or individual skills don't matter. Yay.