Its probably closer to this, lusche:
Preformance (Plane A)^2 x ( 2xSkill (Player A)/3)^3 vs Preformance (Plane B)^2 x (2xSkill (Player B)/3)^3.
It seems that at low skill levels, preformance is by far the determining factor. But at high skill levels, the factor that skill plays into a fight increases far faster than preformance, due to the power of 3 affecting skill.