Here's the problem with overly detailed rules dealing with edge cases in D&D.
When you and I play at the table, we don't need those rules. We are perfectly comfortable ruling on-the-spot to take care of the edge cases. Like the FIFA football referees, we see what happened, BOOM, ruling. Done.
However, the corporation that publishes D&D has realized that they sell a lot (like, an obscene amount) of books if they can get a popular Organized Play program going, and then drive the sales with specific adventures. During the 3.5E RPGA era, they had this down to a science. Say, they come out with Sandstorm, a book about desert campaigns. It's meh. On it's own, it might sell okay, some people still have nostalgia for Al Qadim, they put some references in there, okay. Fine. However, then they release a season's worth of scenarios in their Living Greyhawk campaign, which has 50,000 active players worldwide, and they use Sandstorm extensively. Like, they allow new player options from it (none of which have undergone thorough playtesting), all of the adventures take place in the Bright Lands (a massive desert), they use monsters from it (which have never been in the Bright Lands before), etc. All of the sudden, DMs who had been running Living Greyhawk need to pick up the book, because they need to refer to spells from it (which are new and have never been seen anywhere else). Players need the book because they heard this one prestige class has great synergy with something their character does, and there's this broken magic item in it, and did you see they had rules for centaur characters...
Suddenly, convention organizers need to deal with thousands of new edge cases. Every four months. And when a DM just makes a ruling on the spot, that isn't specifically spelled out in the rules, the players complain and report the DM. And nobody wants to be blacklisted, because the program puts hundreds or thousands of butts in seats at the convention, and if I want that free DM pass I need to be able to run those games, which I can't do if I've been banned from the program.
It was a very effective marketing program at that time, is what I'm saying, and the rulebooks were being written specifically to try to address that, is what I believe.
Now, under 5E, they went for a more relaxed set of rules, but they're still pretty beefy, and people still love to argue and rules lawyer. I had a player threaten to report me to the convention's RPG Director because I had a barbarian throw a javelin at him when he tried to flee a fight by flying away, as his argument was the barbarian stat block does not include javelins, so they can't have them. All barbarians everywhere use greatswords, because that's what's in the stat block in the Monster Manual.
I laughed in his face, and his complaint went nowhere because I was the RPG Director of the convention and the ultimate arbiter. But that is the kind of player that the rulebooks are written to try to address. They know the rest of us will just ignore what we don't like anyway.
