You really need to get out more, meet people, learn how the memory of man is able to pack data.
People who work extensively on government regulations MUST commit the existing structure and text to memory ~ or to heart as the ancients would say. Only then can they CATCH and CORRECT the errors the mechanical processes create in any text! That means that somewhere there is someone wholiterally knows the federal tax code. Somewhere else there's a person this very day who KNOWS the USPS book of books, the Domestic Mail Manual.
And just where does the person get the information in the first place.
I think what people fail to see is the difference between being familiar with a written work to recognize errors in implementation of it, and correcting a written work based on oral teaching.
Since the written work is WRITTEN down, it can be referred back to for veracity. That cannot happen with oral tradition unless that oral tradition is immediately and faithfully recorded. At which point, it becomes a written work that can be checked for fidelity.
oooops.