This book is one of the pocket-sized go series published by Yutopian Enterprises. I really like pocket-sized go books because when I travel, I can take them with me. Whenever I am on an airplane, inside a car, or get bored, I just take the book out of my pocket and start doing some practice problems.

There are 80 problems about 3-4 joseki, mainly about how you should play when your opponent deviates from joseki. For each question, there is one diagram for the "Correct Answer," one for the "Variation," and one for the "Failure." I love the book because the question is on one page, and the answer is on the next page, so you will not accidentally spot the answer.

I have realized that this book is very useful for learning how to play an opponent who does not like to follow joseki or when you play black in a handicap game. When I was a low kyu player, most of my opponents did not follow joseki at all, and now that I am a high kyu player, I have found out that many of my opponents deliberately do not follow joseki. This book teaches you how to effectively prevent your opponents from tricking you, and it might even give you inspiration to trick others.

This is the second volume in the author's Pocket Skills Series. For a description of the format of the series, see the first book in the series; like it, this book is a pocket-sized problem book with 80 problems.

Before reading the book, I wasn't too excited about it. I didn't expect learning about tricks in joseki to be a useful way to spend my time (I'm an AGA 1k, for what that's worth), and reading the only other book in English on the subject didn't change my mind on the issue.

But, as I started reading the book, my opinion changed: it's really rather good. Thinking of this book as a way to learn about how to deal with trick plays in the opening is misleading. Instead, it's a book that will help hone your judgment and reading in opening situations, so you can look at a corner position and figure out which side (if any) has the advantage.

Of course, a large component of learning how to evaluate corner positions in the opening involves seeing joseki: that way you get a feel for what a fair trade will look like. But that's a fairly passive process: to really learn the subject, you need to solve some problems, to give you practice thinking about the subject in situations that mimic live games.

And here, there's probably a didactic advantage in having the problems not present even situations, but rather situations where one side has an advantage. For one thing, it's probably easier to detect situations where one side has an advantage than situations where the sides are balanced: it gives you something a bit more concrete to point at. For another thing, unbalanced situations won't be ones that you have memorized from joseki books, so you won't use your memory as a crutch at the expense of developing judgment. Finally, kyu-level players diverge from joseki all the time, so perhaps it's more true-to-life to see problems where one side diverges from joseki.

At any rate, that's my theory. So: what about the book itself? Like I said, I enjoyed it; I thought the problems were good, and it helped me focus on something that I'm not very good at. I read it at a fairly fast clip, and that's not the way to get the most out of it: this book would be great at a problem-a-day level; if you wanted to finish the book over a month, maybe a problem-a-meal would be a nice tempo.

Which launches me into another theoretical digression; I seem to be in the mood for those today. Which is: joseki problem books are hard. And there's good reason for that. On the one hand, we can contrast them to life-and-death books. These books have the advantage that you have a concrete goal in mind; while they require in-depth reading, that reading is at least confined to a relatively small area, and pattern-matching can be a quite effective tool here. On the other hand, there are large-scale problems (e.g. whole board opening problems); these are largely tests of judgment, where most of your energy is spent on figuring where the biggest/most urgent positions are. You have to do some reading to figure that out or, once you've figured that out, to decide upon exactly the right place to play, but basically they're tests of judgment as opposed to reading.

But the problems like those in this book combine both reading and judgment in a particularly annoying way. Like life-and-death problems, you really do have to read out how the exact position of the stones affects matters, how playing a stone in one place rather than another might make a crucial difference in a race to capture. You might not have to read quite as far or as broadly in a life-and-death problem; on the other hand, your choices aren't quite as geographically constrained, either. But, along with this reading, you have a real test of your judgment skills: you can't just look at who lives and who dies, but rather how much the territory and influence that the sides get is worth. So you have the detailed reading of life- and-death problems combined with the amorphous goals of large-scale problems.

So: read the book, at least if you're a strong kyu or weak dan player. (Probably even if you're a strong dan player.) But keep two things in mind: the first is that you should read through the problems slowly, considering all the different possibilities, because that will put you in the best position to learn from your mistakes. And the second is that you will make mistakes while reading the book, so be prepared for that: it's a learning experience, not a coronation of your abilities. (Or at least not a coronation of my abilities!)