I'd guess (and i feel like i might have suggested at the time) that its the same principle as the "why can building roads make the government's job harder?"--the normal chiefs just ignore some stuff, either on purpose or on accident by being overworked. Rulwyna and the rest of the Crow Triumvirate were so skilled and dedicated that they could and did do all the theoretical jobs for hte king and chiefs that usually went undone or half done because it wasn't practical. The normal chief gets through the building permit oversight in an hour because he just checks off all the ones by other chief families because he 1. legitimately trusts them to do their work and follow standards (and who cares if they skim a bit off the top, the People are rich and he couldn't do this without the other Families!) or 2. is being bribed to do so. Besides, he knows as much as most, but he's better at diplomacy, not building, so any actual problems, the admin chief would've caught! Therefore the only ones he has to check are the ones from newer families, and even then the nitty gritty checking is done by the admin chief. He just checks general zoning or if it'll affect future plans. Rulwyna, on the other hand, takes 4 hours to go through the same work, because she actually checks all of them, and she knows all about the nitty gritty, so when she seems fudged numbers, she sends it back for review, or if it looks like a mistake rather htan graft, she just fixes it herself.
@Academia Nut that sound about right?