While that is technically true, it sort of ignores the problem. There is no ambiguity with bonuses that are not percentage-based. Other effects which have no associated stat, like evasion or attack speed, and those necessarily have to be tested to know (and I don't think anyone ever determined whether Featherfoot is additive, multiplicative, whether or how it stacks with blind, etc). However, FFXIV has stats affecting percentile values which are themselves not percentile values, like critical hit rate. Inner Release description states: "Increases critical hit rate by 30%." What it actually does is increases the chance to critical hit by a flat 30%, and it does nothing involving the critical hit rate stat. This would have an exact analogue in the description of Berserk, which states "Increases attack power by 50%, except that ability does exactly what the description states -- "Increases [stat name] by X%". It just ends up being pretty sloppy.
