Your later point is the one that concerns me. Organizations like governments have issues where the spirit of the law is valued over the letter due to inertial restrictions over revising the law - when it comes to private corporations the ability to restructure rules remains unless it's explicitly surrendered. In these cases keeping the set of rules exposed to the public (and even demoing changes) can allow revisions to those rules to increase their accuracy.

And, when you get right down to it, any rule that isn't well structured will be exploited by bad actors, people looking to roll out malicious browser extensions have a strong motivation to try and discover those rules with a high level of accuracy by testing them - only the good actors remain uninformed.