Carl Meir’s introduction to this indicated that it was first created for the German Experimental Circle and then made available to the UK circle prior to its 1951 Michaelmas conference so it could be ruminated upon in advance.
What is pivotal about this is that the medical section reached out to the BD movement with tactful suggestions about how the models upon which the two disciplines worked might be harmonised. In brief, especially due the publications of Guenther Wachsmuth, BD was proceeding on the understanding that the ethers were all that was responsible for plant life because plants only had a physical and etheric body. (A fudge was made for the astrally ‘kissing’ the plants.) However, this publication works upon the understanding that plant life is the result of the spiritual working through the astral and through the etheric to be formative. Although the former two are macrocosmic the story is unbalanced and incomplete without this clarification.
Glen Atkinson has gone on to clarify the importance of this issue in his own work in which he uses it to resolve the ‘contradiction’ between lecture 2 and lecture 6 of the Agriculture Course – particularly here and here.