Circuit joining procedure is almost as old as aviation, and the basic rules have changed very little over the years, what does it say about many "modern" pilots that Australia now needs something as longwinded as the present CAR 166, which is about twice as long as the previous, and, in the "good old days" hardly existed as a regulation at all.
You know the answer....Lawyers and public servants building empires to justify their existance.
I never needed a massive pile of CAR's to teach me how circuits should work...its not that complicated.