For me it was nothing short of revelational. It explains a number of historic events with the knowledge of an insider.
This is not someone who sits in his armchair dreaming up wacky conspiracy theories, but a narrative from someone who has been in the midst of those events.
And although it primarely deals with the economic side the story is drenched in oil.
Pity though that he didn't talk more about the middle east and the connections between SA and the US. I found that one of the most interesting parts of the book.