chief obstacle to the spread of G's method

I am reluctant to describe any of Gurdjieff 's spiritual exercises, as I am sure that they should never be undertaken without supervision by some experienced guide. Herein indeed lies the chief obstacle to the spread of Gurdjieff 's method. His pupils are generally agreed that at least seven years of intensive training are needed to form a group leader. The majority of those who attempt this training fall by the way or become so acutely aware of their own defects that they refuse to take responsibility for others. In consequence, those who have at different times accepted the task of guiding others have been overworked and overstrained. Dependence upon highly trained and rarely equipped teachers is a serious defect for which it is difficult to see a remedy.

J.G. Bennett - Witness p.246