This book has been very helpful in causing me to reevaluate pawn moves and their consequences. A simple pawn thrust, well timed, can be a terribly frightening weapon. This book gives you better judgement when to make such moves, and which to watch out for. It will hone your positional understanding of many positions, especially the tangle of Sicilians.
I'm rated approx 2000, and think this book will be challenging, although still insightful, for anyone <1800.
