I believe that GM is indeed the father of the crest release (and the puke green breeches) - both designed for easy identification of his students. And of course, spread like the plague once realized, since ‘if his students do/wear this, it must be right’… I do not for a minute believe that he ‘invented’ the crest release to become what it’s become - a crutch for unready riders to jump sooner and ‘bigger’ than they should. I have far too much respect for his knowledge and ability and standards to imply that. However, it’s far easier for wannabes to lean on the neck than to develop an independent seat, enabling them to follow their horse’s head/ neck movements softly. I believe we used to call this ‘grabbing mane’?! OK OK - I KNOW that one doesn’t actually grab mane in a crest release - but it sure allows more ‘outside support’ than the free hands of an auto.
And, of course, I’m not implying that ALL eq riders pose.