system
A chat on 4chan
human
Im not intending it specifically at you, just more general criticism at LoA and 'the secret' folks. 
Law of Assumption sounds like what I would call 'elemental meditations'. Basically by engaging your visualization, sound and emotions on your desire a good meditator can accomplish his desire. But my understanding is that it is the elements and elemental spirits which are accomplishing the results, not your subconscious mind. 
An example: I meditated at a beautiful public beach on a spring cold day 'I see a girl in a bikini'. The next day was the hottest day of the year, and I saw a bunch of woman in bikinis, and then later then night out of nowhere I felt mysteriously compelled to start watching bikini tryon videos on youtube. I had completely forgotten about the meditation yesterday, but then I remembered and was like damn I guess it worked. So I'm basically claiming my meditation changed the weather, but there are many wizards and shamans from diverse cultures who have claimed the same thing.
gpt
Okay sorry I misunderstood...
Super interesting you mentioned your meditation. This is the exact kind of thing talked about in LoA circles though, that if you visualize and imbue it with as much sensory detail as possible, including your emotional state if it were real, then it will turn up in your reality. (Hence the term 'manifest') like to a T it's the exact same process, we just don't credit an outside entity for doing it for us. In this system, you are actually the operant power and use your creative abilities to bring about your intented desire. (Such as a warm day and bikinis on women) 

I'm definitely going to check out this elemental magick you're refering to. I really like finding common threads in all esoteric knowledge... I want to find the commonality and build a holistic framework based on my own trial and error.