dolpinsky DCT's Booklet?
So far, of the few reading materials I have come across... they all taught similarly, but I just started studying two months ago and have yet to buy more books, so I cannot tell you how "different" the booklet is from what others are reading. But skimming though it seems to have answered a lot of technical questions that surfaced in this thread the past seven years.
I have no idea how well the book will serve me in the long run. Neither have I any idea of how diverse the technical questions will get in the actual interview.
It will serve well as a starting point of what to study and further investigate, but it should definitely not be the only reference material you use if you want to ace stage 2.