I finally got a copy of this book, and after spending a couple of days with it, I'm extremely happy; it's an excellent book!
Pert does an admirable job of trying to make this a complete repertoire against 1.d4 d5 2.c4. He gives 2...e6 3.Nf3 Nf6 4.Bg5 Bb4+ serious coverage, which is a line that I've discussed (briefly) here before and always been curious about. His analysis goes much further than I've seen before.
He makes a great case for 3.Nc3 Bb4, which I've always been skeptical of. Many players will use the Ragozin as a companion for the Nimzo-Indian Defense and so won't need this portion of the book, but I'm impressed with it. I'm not quite as high on the Black cause as Pert seems to be, but it's full of ideas to pose new or different problems to White, which is all you can really ask for. For instance, 1.d4 d5 2.c4 e6 3.Nc3 Bb4 4.e3 Nf6 5.a3 Bxc3+ 6.bc c6!? allows Black to still pursue a "Light Squared Strategy," answering a later cxd5 with ...cxd5 and not transposing to potentially problematic Nimzo lines. It's interesting and stimulating, though I'm not sure that Black is truly equalizing here.
White can use the move order 4.a3! (my annotation) 4...Bxc3+ 5.bc Nf6 6.cxd5 exd5 7.e3, which avoids those ...cxd5 ideas mentioned above. Pert does a good job with his coverage here, and I come away thinking that Black's position is not as bad or lifeless as I've always thought. However, Pert mentions in a page-long note that Black could try 5...c6!? to get back into the 6...c6!? lines:
Here he only analyzes 6.cxd5 cxd5 7.Bf4, saying that 6.e3 Nf6 transposes elsewhere in the book. Unfortunately, 6.e4! is a position from the Marshall Gambit Declined that has scored very well for White, usually arising by the move order 1. d4 d5 2. c4 e6 3. Nc3 c6 4. e4 Bb4 5. a3 Bxc3+ 6. bxc3. It's playable for Black, but there's no coverage in Pert's book at all, and in my opinion, it's very dangerous to face over-the-board.
Also in the main of the 4.a3! Bxc3+ 5.bc Nf6 6.cxd5 exd5 system, he follows (by transposition) Hillarp-Persson - Rozentalis, Gausdal 2006.
Pert ends his analysis after Black's 14th move saying that "the players reached a complex middlegame with mutual chances," and then "Black has stabilized his position and followed up by placing one knight on e7, supporting g6 and d5, and the other on d6." He doesn't give the concluding moves of the game or analyze any alternatives, which I think is a real shame, since to my understanding this is a very critical test of Black's 3...Bb4 system! I understand that no other games reached this position, but some guidance and independent analysis would really have helped. To my mind, White has his two bishop, queen, and both rooks on their original squares, and despite it already being move 14, I wouldn't think that the opening is over.
Pert does a great job in the anti-Catalan chapter from what I noticed; I haven't looked too closely there, though I play the Catalan! A few lines look a little boringly equalish, but I suppose that's life.
I don't have a ton of experience in the Ragozin proper; I've tried playing it over the years, but always struggled on the Black side of the Westphalia or Manhattan variations. I didn't like the lines where Black played a quick ...h6 and ...g5, either, so eventually I just gave up. Here I think Pert's book shines, though! He offers 5.cxd5 exd5 6.Bg5 6.h6 intending a quick ...g5 and ...Nf6-e4 as his main system, but as noted he also gives 6...Qd6!? as an alternative, spending about twelve pages on it. My initial conclusion is that this is fully playable for Black and that it solves my personal problem of what to play in this line; hurrah!
Again as already noted, he gives the Vienna transposition after 5.Bg5 dxc4, and now both the main line 6.e4 c5 and 6...b5!? for Black to choose from. I'm glad to finally see some serious Vienna analysis in print for us non-professionals, and while my knowledge of these lines is very limited, my impression is that he does a fantastic job guiding us through the move orders and critical lines, suggesting some very interesting novelties along the way.
In all, I personally find this a fantastic book! The highest praise that I can give it is that it's finally convinced me to play the Ragozin, solving my own personal reasons for avoiding the opening in the past. The crux of the matter, for me, is whether 6...Qd6!? and the Vienna hold up and suit me, but my initial impression is very positive. I've played the Noteboom/Triangle and Semi-Slav in the past, so I'm familiar with similar positions, and I see many of the less critical lines as improved forms of the Noteboom or Semi-Slav. I'll have to learn the Vienna variation now, but, I've been looking for a new defense to 1.d4 for years, and this seems to be it.
In all, I haven't been happier with an opening book purchase in recent years, except perhaps with Lokander's book on the Open Games. I just hope that there's still some surprise value left down here at the under-2400 level in the US!