Evasion:

Why is the numerical value of our Evasion stat hidden? Or is it a set Rate?

Does Evasion have a hidden numerical stat value? Or is it merely a --% chance of Evading attacks depending on Monster level and accuracy?

How should we interpret skill descriptions such as Featherfoot regarding changes in Evasion?

Featherfoot: Increases evasion by 15% Duration: 15s

Does this modify a base value by 15%? Or does it adjust a --% chance of evading?

If the latter - is this --% chance of evading modified as multiplicative or additive?

Thanks to anyone... (devs?) with the answers to these questions.