I would disagree on two items. First, it does not remove the idea of personal judgment. I mean... I'm responding to
@Crimson Longinus about exactly that. The personal judgment of the GM is not absent, it's just used in areas other than the resolution of actions with uncertain outcomes.
Second, it's not about preventing abuse so much as it is about creating a complete set of rules. Why leave room for error if you can create a system that doesn't leave room for error? Also, I don't think that it needs to be about "abuse" or "bad behavior" so much as conflicting ideas or a bad judgment call.
As a GM I've made plenty of poor judgment calls over the years. Especially in my earlier days. The more room for error a system has, the more likely I'd make such a poor call. These poor calls aren't done out of some sense of maliciousness. They're not about abusing power.