An untrained layman can only understand canon law up to a point. "Reason" is not sufficient to fully grasp all the nuances of the legal system.
I can read 10 books on how to rebuild a car motor, but that will only get me so far. If i've never worked in a mechanics shop to ACTUALLY rebuild a motor, then I won't be able to do it. "On the job training" and certain "industry knowledge" is essential.
I can't believe you are actually arguing that a person will no legal training can fully understand canon law.
That was when I turned off Ann Barnhard's video about the Bennyplenism. She started out with a 10-minute rant about how anyone can understand Canon Law and that's it's simple and that she would womansplain it all to everyone. No, it's not simple. CL is filled with technical legal terms that one would have to know a lot to propertly interpret. It's why they offer advanced degrees in Canon Law that take a few years to obtain.