The core of Alexander's method is the internal and subtle work, a small yet major difference that simply can't be perceived with naked eyes. Not even by attending his workshops one can easily capture what lies behind the curtains, the vastness hidden behind the classical self-defense demonstrations. What is shown is just the tip of the iceberg, a tiny portion that doesn't represent the profundity of it. There is only one way to get it straight and that is to taste it oneself. In other words, to have a direct experience in the body through a tactile interaction with the master. And even like that, it still needs time for the body to process it to the point when the mind would eventually get properly aligned with the experience and thus become ripe enough to sketch some right ideas on this unorthodox approach that seems to challenge traditional physics and biomechanics.
Trying to find explanations with intellectual faculties solely is a serious mistake. The analytical mind is the wrong tool to grasp how Alexander works. It would only generate more confusions and unnecessary conflicts rather than dispelling the aggressive skepticism that I've noticed going on around FB threads. In my opinion, those who are not control-freaks, prone to face the unknown comfortably, free of preconceived ideas with open-mindedness, are the ones who usually harvest the benefits.