It's a tricky proposition to do an openings book with dated analysis, and while the publisher takes a shot at pulling it off by providing some contemporary commentary, the two cooks don't really improve on the soup. IM Purdy was a strong player (four times champion of Australia, and the first World Correspondence Chess Champion) and writer (publisher of Australasian Chess Review, Check, and Chess World). Bobby Fischer has spoken highly of Purdy's analytical talents, and Thinker's Press has published several books of his analysis and insight. Those are mostly excellent books that concentrate on his writings and teachings, and aspiring players would do well to check them out.

While Purdy is an insightful author, this book is more about opening lines than concepts, and I think its age shows. The publisher would seem to agree with this concern, because he enlists NM Ronald Wieck to provide running commentary throughout the book, mostly to discuss changes in the theory of the lines since Purdy's day. While this is an interesting choice for a revision method, I don't think the book pulls it off.

The primary problem as I see it is that too often Purdy's conclusions, upon which his opening ideas have been based and discussed in the main text, are shown to be different than modern theory would suggest. While this is understandable, given the age of the analysis, I think it is going to confuse the reader and lead him to doubt the concepts that the author seeks to discuss. 

Purdy's book is based on providing an all-purpose repertoire for the black player, and he mostly concentrates on the structure with black having pawns on e6,d5,c5, and b6. This is a sold structure that can arise from the French Defense against 1.e4 and from the Queen's Gambit Declined against 1.d4. There are also a variety of methods for achieving it against many other first moves for white. It is a viable and decent choice for a black player seeking a defensive structure.

Indeed, if the publisher had chosen to include much of Purdy's explanatory text, such as the introductory chapter on Opening Problems and Principles, and the chapter sections that discuss opening play in general, and had gotten another author to interweave his analysis with that of Purdy's that stands the test of time, this might have been an outstanding book. As published, it has too many confusing parts, where players have followed along with Purdy's moves and prose, only to find at the end that the author may have misspoken.

My second major concern with the book is the inclusion of a section on the Accelerated Dragon Sicilian (1.e4 c5 2.Nf3 Nc6 3.d4 cxd4 4.Nxd4 g6). While the book mostly covers a solid multi-purpose black repertoire, it veers off to include 31 pages on an extremely sharp line that isn't exactly in keeping with the rest of the suggested repertoire. Further, here a lot of the analysis is dated, and the forcing nature of the lines suggests to me that the black player relying on it for opening preparation will run into many headaches. I've played this variation many times, and I would not recommend it to anybody based on the analysis contained in this book.

My final concern is that the layout of the book leaves way too much unused space within the book's listed 192 pages. The book is 6" by 9" but the main column spans slightly less than 3 inches across. There is a second column, of slightly more than 1.5" on each page, but it only contains the footnote-sized commentary by NM Wieck. This is a curious and wasteful layout. The book could have been compressed by running footnotes at the bottom of the page, as is standard practice.

Indeed, of the 176 pages of the book that use this format (the title pages, table of contents, editor's forward and commentator's preface span the first 12 pages of the book), 52 have no substantive comments in the footnote column, and another 68 have no more than one substantive comment (often little more than one or two lines). Thus fully two-thirds of the book consists of pages with a second column that is entirely or mostly blank (analysis-wise; we do get pictures of the Purdy's, other chess players, and other books published by Thinker's Press). Indeed, I found only 10 pages where I felt the material justified a separate column. As a player who must often rely on the stated number of pages in a catalogue to gauge content, I find that type of layout to be at best wasteful and at worst something worse than that.

In conclusion, this book, both because of the age of the material, the manner in which it was updated, and the way that it is presented, doesn't really provide value to most players. If you're a Purdy fanatic or believe that the repertoire presented will be a useful complement to other books, you might want to check it out. Otherwise, I'd shop elsewhere for a "24 hour" repertoire.