gowan wrote:Ishida's three volume dictionary was first published 33 years ago, translated from an even earlier Japanese edition. As a result much of the book is out of date. Especially the part on 4-4 point joseki is weak. A lot of developments in 4-4 point joseki occurred after the Ishida books were published. In the other volumes there are variations listed as joseki, i.e. even results locally for both players, but which are no longer considered joseki by professionals. A new edition in Japanese was published in 2009, edited by Takao Shinji. Ishida's disctionary is so old ... we need a newer version. I hope the Takao edition will be translated.
There are two aspects to studying joseki. First is the idea of a sequence of moves locally giving an equal result. Studying these you can learn a lot about positional judgement, shape, and tesuji. The idea is not just to memorize sequences of moves but try to understand why each move was made, what is wrong with alternatives, and how to take advantage of errors. This is a life-long project. The second aspect is learning when to play joseki depending on the whole board position. Probably the best book about this is Yilun Yang's Whole Board Thinking in Joseki These books give you wonderful knowledge of how large scale issues affect somewhat distant corner developments.
Another way to study joseki is to play through lots and lots of pro games, watching what they do in corner sequences.
It doesn't matter if Ishida's is out of date. If you study the book, read the explanation, and think for yourself, it is still a great resource.
Ishida's gives sequences that are said not to be joseki. But seeing the sequence and learning about the thought process is still most important. I recommend getting Ishida's, but just remember: think for yourself. You should do that with any joseki book, anyway.