From JJ himself....quoted from his 20th anniversary retrospective note (in 2018) to the dive community.
“The tagline I chose for GUE, “Quest for Excellence”, does not presuppose universal correctness. Rather it is a quest for divers to get the most they can out of their diving and their lives. Likewise, our dedication to a standard approach is not meant to imply that nothing else will work but rather that teams of divers organized to use a common platform will reduce stress, encourage safety and have more fun.”
I think when some of the zealousness comes into play it’s a result of GUE adherents who have never been part of a strong team environment (where lives depend on equipment and teamwork) and their dedication to complying with some common practices overcomes their real experience.
I’m confident that adding a D-ring to my right waist band is not going to make me a sub-optimal diver. I don’t have any problem deploying (and stowing) my 2m hose and my desire to fly a balanced set of deco bottles outweighs my need to rigidly adopt a standard without the benefit of thought, rehearsal and experience.