Rudolf Steiner "Knowledge of the Higher Worlds"

Steiner in this book lays out a path of initiation, climbing the ranks of "imagination, inspiration, and intuition", in order to consciously enter the supersensible worlds. He details meditations such as concentrating on the feelings of plants growing/decaying, comparing the essence of a crystal to a desire filled animal, meditating on how a seed contains within everything in it for life ect. I am wondering of the relationship to this type of initiation to the dialectic of consciousness in "Revolution of the Dialectic". Samael Aun Weor said that Steiners teachings were incomplete, but that they were wellsprings of wisdom. What is the difference between the Illuminating Void and the knowledge gained with Imagination ect., and should they be both pursued at once, doing exercises to quiet the consciousness/reach samadhi, as well as develop faculties of soul to sense higher worlds? Should one pursue these two types of knowledge in any particular order? I have started both systems and am seeing the effects of each. Any and as much detail on this would be greatly appreciated.

Here's a link to his book: http://www.hermetics.org/pdf/steiner/Rudolf_Steiner_-_Knowledge_of_the_Higher_Worlds.pdf