The problem is that everyone understands Gurdjieff in his or her own way, with specific reference to their life experiences. The question is then whether these fifth and sixth hand primers on Gurdjieff should be published at all, considering that they are bound to contain much that is subjective or even misleading. Gurdjieff himself constantly warned his students about this and it is also where Orage went wrong.
As far as I'm concerned, the acid test is whether or not the writer has something new - and specifically something practical - to bring to the table. Something from their own lives For example, Ian Phillips Lawrence was able to bring his knowledge and experience of acting in The Good Obyvatel, the only book I've found at all useful outside of Gurdjieff's immediate entourage.
If not in my opinion the reader should stick with Gurdjieff's own writings. And those of his students who new him in the flesh and can recount his words in the context of work arranged by him.