From memory, it's a long time since I read it, in the intro he says something to the effect that this is written for my colleagues in the SWP to be the final arbiters of and I don't care for the judgement of any others.

At that point it couldn't go any further down hill, it was written as a point scoring exercise for one faction of the left over another faction. That central bias weakens it as a work that could have been a fascinating treatise and looms as the elephant in the room over it's many pages.