evasion skill > evasion. plain and simple
think of it like this. every time a mob attacks you you have a chance of evading, like rolling a dice.
lets say the numbers are 1-100, 1 beeing 1% chance 100 beeing 100% chacne. well you evasion skill caps the highest number you can roll. evasion raises the lowest number you can roll.
the higher you evasion skill is also raises the lowest number you can roll. but evasion doesnt raise the highest you can roll.
only evasion skill.
so to make things simple evasion skill > evasion