I'm only 20% of the way through this book, and I don't like reviewing books before I finish them, but I have already gotten my money's worth, and I don't want to wait a year before raving about it. In addition, I haven't seen it discussed at all, so perhaps many people aren't aware of it.
One little project I have often considered is to take a few tsumego problems that baffle me, present them to the strong players here, and say "Exactly how did you solve this? What features did you look for, what vital points jumped out, what tactical tricks leapt to your mind?" Tsume-Go Strategy
does exactly this for 47 corner problems from the Gengen Gokyō
. Each problem is dealt with in exhaustive detail, starting with a "Hints" section listing all the most interesting features of the problem, continuing with a tour of all reasonable variations (including bad or insufficient moves and their refutations), and finishing with a "Lessons Learned" section summarizing the general principles that the problem illustrates.
Each subproblem is presented as a separate problem, so even if you get the main problem wrong, you have plenty of chances to solve the simpler problems that it depends on.
One additional nice feature is that the nature of every ko is explicitly spelled out. No simple "Black lives in ko"; each time, it is noted who has to make the first ko threat, and whether there are any approach moves for either player. The ko threats and responses are explicitly "played out" in a separate area of the board to make it clear who's getting compensation elsewhere on the board, a technique that I have myself found effective in the past.
This is definitely a very "Western", scientific, approach to tsumego, which might not meet with everyone's approval, but for those who like to learn this way, the book is a gold mine.
It is available only on the Go Books app, and is a perfect fit for it. For one thing, a printed copy of the book would probably be well over a thousand pages, and would feel very bulky; here, if some explanation feels trivial to you, you can just skip over it and continue. There is also copious hyperlinking, so for example if you considered a move but it is incorrect, you can easily jump directly to the refutation.
The writing is very clear and idiomatic and I am almost never aware that English is not the author's first language. I particularly appreciate the gender balance (White is always referred to with female pronouns).
I think that 10k is strong enough to get a lot out of the book (you could even just skip the top-level problems and just solve the subproblems on your first read-through), and I imagine it would be useful to any single-digit kyu player. The author is only a strong SDK himself, but tsumego seems to be his specialty and everything so far seems to be accurate.
Redecker has two other books on the Go Books platform, Tsume-Go Strategy 2
(dealing with side patterns), which I will certainly read too, and Workbook: One-Move Life and Death Problems
, intended for beginners. From the free preview of the latter, I fear it may be so exhaustive as to be exhausting, but maybe many readers will find it to be exactly what they need.
I heartily recommend Tsume-Go Strategy
to any SDK (and potentially weaker and stronger players as well) who wants to acquire better skills at tsumego and reading.