9...a5 Against the Bayonet: When an Opening Book Is Sold as an Antidote

I reopened my old commentary notebook from 2026, where one page carried a hurried note after a national chess championship final: 'Win with a move your opponent has never seen, not with a better move.' Today, reading a new opening book that recommends 9...a5 against the Bayonet Attack (9.b4) in the Classical King's Indian Defense, I heard that old note echo back. The seller calls it an 'antidote' — something that leaves the computer not knowing how to handle it. But I have watched enough games to know that no single move is ever an antidote; it is only an invitation. Context: Mar del Plata and the 9.b4 thrust The King's Indian Defense (1.d4 Nf6 2.c4 g6 3.Nc3 Bg7 4.e4 d6 5.Nf3 0-0 6.Be2 e5 7.0-0 Nc6) is one of the oldest and most dramatic opening systems in chess. After 8.d5, the center locks, and both sides begin a race of flank attacks — White toward f2-f4, Black toward...f7-f5. The Mar del Plata Variation, where Black develops the knight to e7 and then h5, has been a classical battlefield for decades. But the classical Mar del Plata era has changed. Around 2026-2026, grandmasters began employing 9.b4 — the Bayonet Attack — a fast pawn thrust aimed at disrupting Black's queenside pawn structure before Black can organize a kingside assault. The Bayonet is not a recent discovery; it has been mentioned in books for a long time. Its popularity surged, however, when computer analysis showed that if Black replies in the traditional way with 9...Nh5 (opening the position and forcing White into concrete lines), the game transitions into extremely complex variations where a single small mistake can lead to immediate defeat. Against that backdrop, the new book proposes a different path: 9...a5! The move 9...a5: A strategic idea or merely a good move? The first point to note is that 9...a5 is not a novelty. It has been present in opening databases for many years, and top grandmasters have used it in important games. The book does not create a novelty — it repackages a known choice as a 'strategic solution.' Positionally, what does 9...a5 aim to achieve? First, it prevents White from advancing the pawn to b5, keeping Black's queenside pawn structure intact. Second, it opens a counterattacking avenue on the queenside, where Black can push...a5-a4 to create pressure. And most importantly, it avoids the forcing lines of 9...Nh5, transitioning the game into a complex positional state where 'strategy matters more than tactics.' This is a valid idea. But validity is not superiority. The promise that 'computers cannot handle it' The book promises that 'computers often do not know how to handle the complex strategic positions that arise.' This is a marketing claim, and I will say it plainly: it is outdated. Since around 2026, engines like Stockfish NNUE and Leela Chess Zero have evaluated closed King's Indian structures quite reliably. They no longer 'do not know how to handle' these positions — they handle them well, and in many cases they show that 'strategically complex' positions can be resolved through precise calculation. I recall the words of a grandmaster I interviewed many years ago: 'The computer does not understand strategy, but it understands outcomes.' And the outcome, in most Mar del Plata positions, can be reached through sufficiently deep calculation. The claim that 'objectively the chances are equal, but if Black knows what to do, the position can quickly become dangerous for White' is honest but unquantified. 'Dangerous for White' reflects practical difficulty — the psychological burden over the board, the asymmetry of the position — not an objective edge. This is an important distinction that buyers need to understand. From DVD to digital platform: A trend in motion This book is sold as a DVD — a format I have been familiar with since the 1990s, when I was still a player and used ChessBase discs to prepare for tournaments. But the world has changed. Today, online platforms, continuously updated databases, and free analysis tools have eroded the value of DVDs. This is not a criticism of this specific book, but an observation about the industry. The value of opening preparation is shifting from static media (books, DVDs) to dynamic digital services, where data is updated daily and users can immediately check a new move with an engine. Target audience: Club players, not grandmasters Interestingly, the book does not mention any grandmaster. There is no Elo rating, no performance record, no head-to-head history. This is an opening book for club players — those who want to build an opening system without memorizing hundreds of forcing variations. And this is where I see real value: the idea of 'strategy over memorization' is a good one, especially for amateur players. But it needs to be presented honestly, not by exaggerating the value of a single move. No single move is ever an antidote I have watched thousands of games over 49 years of following chess, and I have never seen a single move that 'neutralized' an entire opening system. 9...a5 is a valid choice, but it is only one part of a larger system. Against the Bayonet, Black needs more than a move — Black needs a plan, an understanding of the position, and the ability to adapt to the different variations White can present. The book promises that 'players who prefer to think for themselves rather than memorize' will find value here. But thinking is not about opposing the computer — thinking is about understanding the position, and the computer, however strong, remains a supporting tool, not an enemy. Conclusion: An invitation, not an answer This book offers a valid opening idea, presented in an exaggerated marketing context. Buyers should treat 9...a5 as a starting point, not as a refutation. And buyers should remember that in chess, there are no 'antidotes' — only long conversations between two players, where every move is a question and every answer is a step forward. I set down my pen and looked out the window — no, out at the window, where the city of Nha Trang was sinking into sunset. On my bookshelf, the old 2026 notebook was still there, with its note: 'Win with a move your opponent has never seen, not with a better move.' I think perhaps that still holds true. But 'never seen' does not mean 'cannot be countered' — it only means the conversation is still ongoing.