Some background for those who haven't yet seen it.
In 1937 a book titled, 'The Middle Pillar', by Israel Regardie was published.
Wrote Regardie:
[Psycho-therapeutic] Analysis is the logical precursor of spiritual attainment and Magical experiment... Not until the mind and the emotional system have been cleansed and unified by the cathartic process... can the full spiritual benefits of magical work be reflected into the mind of man.
...We should remember the parables of the archaic philosophical religions whose fundamental tenet was that within man was a spirit, a dynamic center of consciousness which, because of its contact and association with matter, had been plunged into a profound sleep, a kind of somnambulism...
By endeavoring to extend the horizon of consciousness, to enlarge the field of awareness so as to embrace what previously was unconscious, is obviously a logical method. To become aware of all our actions, our thoughts and emotions and unsuspected motives, to regard them in their true light as actually they are and not as we would like them to be or as we would wish an onlooker to perceive them.
It requires, to take this step, an extraordinary degree of honesty and courage... The more of this suppressed and forgotten material stored in this at one time unknown or dormant side of our nature that can be raised to the clear light of day, by exactly so much do we awake from the inert stupor into which we have in the past been plunged.
It's very likely that Hubbard read these words.
Of course, Hubbard added brainwashing methodologies.
Ideas such as these are part of what attracted many who, then, fell prey to Hubbard's trickery.