The biggest challenge has been to fight against the engines that, at first glance, don't credit this defense with the value it deserves. This is because the engines significantly value the space that White usually has against the Philidor, but there is one aspect that neither Leela Zero nor Stockfish nor any of the other engines take into account – and that is the counterattack!
The aim of this book is to provide the reader not only with a complete repertoire for the Philidor Defense, but especially a repertoire that begins from the very first move – because White has mechanisms at their disposal to avoid entering into the vast labyrinth that they often perceive when meeting this opening. Why do I say labyrinth? Because Black can come up with different move orders that make White dizzy – and the curious thing is that almost all of these ways are acceptable and have good statistics in practical chess. For example, Black may decide to play with ...c6 and ...a5, with ...c6 and ...b6, with ...c6 and ...Qc7, or with ...a6 and ...b6 (which I recommend) etc. In short, I think Black has several schemes, and each one is not very difficult to learn because they have many lines in common.
My goal, as I mentioned before, is to write a book that will become the main reference on this defense and one that will be of help to all types of players, from club players to Grandmasters. For this reason, it was my wish (and I hope I have succeeded) to create a very elaborate repertoire with the firm intention that any player will be able to face an opponent of a higher level, without fear and with clear ideas.
I have tried to include new moves and new ideas against practically all of White's weapons and I have aimed to be as exhaustive as possible, so that I can accompany the explanation of the ideas with concrete moves, to make them easier for the reader to understand.
Clearly 1...d6 and the Philidor Defense in particular, is far from being the refutation of 1.e4 but I have always tried to look for options for Black that are active in order to equalize or to achieve very real counterplay.
Furthermore, the advantage of studying this book and playing this defense with Black is that the chances of White finding new ideas are much lower than in other main openings – such as some very critical lines of the Sicilian, for example, where we constantly see new moves and schemes that quickly land Black in trouble.
Having said all this, I encourage you to discover (if you haven't already done so) this great defense. I hope you enjoy the book and that it will be very useful for your games and hopefully, you will gain many points with the Philidor.
- Sergio Trigo Urquijo