Cho Hun-hyeon's Lectures on Go Techniques
Lectures on Go Techniques by Cho Hun-hyeon, edited by Craig R. Hutchinson, and published by Yutopian (ISBN: 1-889554-42-1) consists of two sections: an exposition on shape followed by 45 early opening problems that focus on positions which arise frequently in games. If one knows a few basic techniques (say 5 kyu AGA), the problems are fairly easy.
The true value of this book lies the numerous solution diagrams. For each problem, half a dozen seemingly reasonable but incorrect alternatives are explored and the reason why each is wrong explained in the text accompanying the diagram. Once the wrong responses have been deal with the correct response is shown and explained. Afterward, there is an additional diagram showing the continuation from the correct answer. As such the book is much closer being serveral professional lessons on the early opening than it is to being a problem book. A player that can identify the possible answers, select the correct one, and know why the other are wrong, would be a mid to high level AGA dan player (3-5 dan AGA).
Example from the Book:
White blocks at attacking the two black stones. Once again, the question is, how will rescuing or sacrificing the two stones benefit the situation? The key is, how to flexibly atari?
Black ataris at to extend his liberties, before cutting at
. After the sequence to White 6, the ladder at a does not favor Black. Black fails.
Black ataris at separating White and completely controls the corner after the sequence through
. However, Black does not like how the two black stones are captured. Black can do better though...
Black should first atari at , forcing White to connect at
, before the atari at
. White the sequence through
, Black cuts White apart and ends with a better shape.
This shows the final position in Diagram 2. Black ataris at without exchanging Black a for White b. As a result, White has no need to connect at b. Thus, play order is very important in Go.