next experiment, I used Susan Polgar’s Chess Tactics for Champions, so I will give it a brief review. This book turned out to be excellent, and served my purpose very well.
The book provides 570 problems at a good price. The problems are both interesting and instructive, with the level of difficulty in a tight range.
My statistics show that I was significantly slower at solving these problems than those in Dan Heisman’s Back to Basics: Tactics.
The problems are not difficult, but the general level is a step up from that of elementary tactics books. I would have thought that this was squarely in the mass market, but had difficulty finding problem books at this level.
The book is split into chapters according to theme, e.g. forks and double attacks, pins. These chapters cover all the main types of combination. Each chapter has an introduction showing several illustrative examples. These introductions are good, but no better than those in other popular tactics books. The final two chapters: Sibling Positions and Twenty-five Famous Combinations do not provide any additional problems. The problems at the beginning of each chapter are easier, but apart from that, they appear to be in random order of difficulty. (It would have been better for me if the problems within each chapter had been reliably sorted into order of difficulty, which would have made my problem batches of more equal difficulty.)
I did not notice any exact duplicate problems, and there are few near duplicates. Three of the problems: p126 #17, p238 #18 and p276 #14 are labelled as White to move, but they should be Black to move. I did not notice any significant errors in the solutions - but I was using the book for speed training - and I am not a Grand Master! I recognised some of the problems from other books, but most of them were new to me.
The diagrams in this book are small, but very clearly printed in the standard chess font on matt finish paper. I found them easy to use for speed training despite their size. The book has is lot of white space with just three (or in some chapters two) diagrams per page. The book has 347 numbered pages (plus some additional pages), so you get a lot of paper for your money. The book also has a quality feel for a paperback.
Overall, the book is excellent, but would have been twice as good if the white space, chapter introductions and the final two chapters had been cut to make space for twice as many problems!