Bayonet 9.b4 and the Move 9...a5: A Chess DVD That Sells Surprise, Not Truth

BAYONET 9.b4 AND THE MOVE 9...a5: A CHESS DVD THAT SELLS SURPRISE, NOT TRUTH Three in the morning in Delhi, and the June heat still refuses to leave the walls. I sat in front of a screen, rewinding a King's Indian game I have watched no fewer than twenty times in my life. On the table, beside a cup of tea gone cold long ago, lay a newly arrived opening DVD: a Black repertoire after 1.d4 Nf6 2.c4 g6 3.Nc3 Bg7 4.e4 d6 5.Nf3 0-0 6.Be2 e5 7.0-0 Nc6 8.d5 Ne7 9.b4. The promise inside was neatly packaged: 9...a5 is the antidote to the Bayonet Attack, and the buyer will not have to memorise many variations. I have been in this trade long enough to know something not especially pleasant. The best opening products do not sell truth. They sell surprise. Surprise, in chess, is a genuine commodity with a real price, but its expiry date is printed very faintly on the back of the box. That night I went looking for numbers to verify the claim. There were none. Not a single reference game, not one database statistic, not one engine evaluation, not even an author's name. Only a very confident assertion and a very loud title. CONTEXT: A POSITION BUILT TO CONFUSE For anyone unfamiliar, it takes three minutes to picture the position. The King's Indian Defence is a system in which Black deliberately concedes the centre to White and then attacks that very centre with ...e5 and ...c5. The Mar del Plata is the variation named after the tournament held in Argentina in 2026, defined by 7...Nc6 8.d5 Ne7: Black pushes the knight to the rim and opens the kingside. In most other openings, complexity is a side effect of the search for advantage. In the Mar del Plata, complexity is the point. The Bayonet Attack 9.b4 is White's answer. White advances the queenside pawn to drive the knight off c6, clears a path for the bishop to e3, and prepares to open the queenside before Black can land ...f5. This is not a novelty. It sits in every textbook on the King's Indian, and it was once the weapon of a generation of leading players. Black's orthodox answer has long been 9...Nh5, a forcing move that sends the knight to h4 or f4, prepares ...f5 and generates direct pressure on the kingside. This is the main line. It has been analysed square by square at the highest level of the game, which is precisely why it is both strong and expensive: you have to remember a great deal. The DVD proposes another road: 9...a5. Black strikes directly at the b4 pawn, gains queenside space, and converts the game from a race of variations into a game of plans. If White captures, Black opens the a-file. If White declines, Black has gained a free move and acquired a target. Both branches lead to a position the books call unclear and the salesman calls strategically complex. One thing must be stated at once, and I emphasise it because it is the entire informational value of this piece: 9...a5 is not an invention, and it is not a refutation. It is a minority but legitimate sideline, which is to say a repositioning rather than a discovery. The promotional material itself concedes that objectively the chances are equal. When a product admits that, it is selling something else: asymmetry of preparation. That is the whole game. Not that 9...a5 is stronger than 9...Nh5, but that your opponent has prepared for 9...Nh5 and has not prepared for 9...a5. WHY VIETNAMESE PLAYERS SHOULD CARE In the chess clubs of Hanoi, Da Nang and Ho Chi Minh City, the King's Indian has long been the opening of people with no time. You do not need to memorise thirty moves if you understand why Black plays ...e5 and then ...c5. Based on my experience following games at youth and amateur events in Vietnam, this is why the King's Indian thrives there far more than many other expensive openings. But that is also exactly the trap. An opening that teaches you plans will punish you most severely when an opponent drags you into a different plan. Le Quang Liem won the World Blitz Championship in 2026 in Khanty-Mansiysk, widely recorded as Vietnam's first senior world title in chess. He achieved it through the ability to handle positions for which no ready answer exists in any book. Nguyen Ngoc Truong Son and Pham Le Thao Nguyen have walked the same road: understand the structure before memorising the moves. That is why a product like this DVD has a real market in Vietnam, and also why it is easy to be disappointed by it. ANALYSIS: THREE CLAIMS, TWO LEVELS OF CERTAINTY To judge its true value, look at the three claims the promotional material makes. The first claim, and the most outdated: computers often do not know how to handle the arising complex strategic positions. That sentence was written for a different engine era. It was true around the early 2000s, when deep-search engines still went astray in closed positions with few forcing moves. Today's engines, built on neural networks and NNUE, evaluate closed, manoeuvring positions with markedly higher reliability. Written in 2026, a sentence like that is no longer a strategic argument. It is a sales slogan. I am entirely certain about the general claim, and only at the level of pending verification when it is applied to this specific Mar del Plata position. The gap between those two levels of certainty is exactly where sellers want the blur to live. The second claim: very few concrete lines, suitable for players who prefer to think for themselves rather than memorise long variations. This is the highest-value and least verifiable claim. The problem is that to play a repertoire built on 9...a5 properly, Black still needs at least three other things. First, answers for every option White can choose instead of 9.b4. White can play 9.Ne1, White can play 9.Nd2, White can play 9.Bg5. You cannot buy an opening repertoire that contains exactly one branch, because your opponent is under no obligation to enter it. Second, working knowledge of the main line 9...Nh5. After Black plays 9...a5, White can perfectly well steer the game back toward familiar structures. The buyer of this DVD will still have to reopen his Mar del Plata book. Third, a layer of understanding about positions for which no definition exists in any book: which Black targets are real and which are illusory. This is knowledge that cannot be memorised, only understood. And it does not come in the box. The third claim: the scope of the product. The promotional material does not state whether the DVD covers only the 9.b4 branch or the entire King's Indian complex after 7...Nc6. Those two things differ enormously in real preparation cost. A set covering only 9.b4 is a chapter. A set covering the whole King's Indian is a bookcase. The buyer has the right to know which one he is paying for, and at present that information does not exist. There is one detail I want to raise that the original material does not mention but a careful reading reveals. The product's title, a night unlike any other, is almost certainly a pun on the military image of a night bayonet assault, tied to the name Bayonet Attack. In other words, the title is promotional rather than informational. That is not a sin. But it tells you exactly what this product is: something designed to sell before it was designed to analyse. So where does its real value lie? In the fact that it targets the right segment: club players rated roughly 1700 to 2200, weekend open tournaments. For that segment, the low memory load claim is a real benefit, not empty advertising. At that level your opponents do not prepare deeply. At that level, a position you understand and your opponent does not is worth more than a position you remember and your opponent also remembers. At national team level the reverse holds. Nobody in the world's top fifty can decline a forcing main line on philosophical grounds. And no coach has ever paid a student's salary with surprise. What is worth noting is that this entire argument requires no game at all to verify. It requires only the right question: what problem does this product solve, for whom, and where is the evidence. Those three questions, added together, take under thirty seconds. Yet in fifteen years in this trade I have rarely seen opening promotional material answer all three. I have spent my career commentating on chess, and I still keep a habit from the years when I was running tournaments: record the position as if drawing a diagram on paper, before allowing myself any emotion about it. The stadium was empty that year, and I found a tactical diagram lying quietly under the seat instead of the roar of the crowd. Chess is no different. Take away the noise, and what remains is what decides. WHERE I COULD BE WRONG Now the part about where I could be wrong, and I must be honest because it is a rule I set for myself after more than forty years of observing this industry. I could be wrong if the DVD in fact covers the entire King's Indian. In that case its value multiplies, and my whole critique about vague scope becomes a critique of missing information rather than of product quality. A communications failure, not a technical one. I could be wrong if the claim that computers cannot handle complex positions was merely careless phrasing, and the author does not genuinely believe it in his concrete analysis. In that case it is a slip of expression, not a slip of thought. I have made exactly that kind of error and been caught on the spot. And I could very well be wrong in underestimating the power of surprise. I once mispronounced a player's name, then read the game correctly the moment the slow-motion replay appeared before my eyes. That lesson taught me that accuracy in small details does not guarantee accuracy in the big picture, and vice versa. The games I have watched at Vietnamese youth events were not won by deeper theory. They were won because the opponent had never seen that position before. The silence of absent applause can kill emotion, but it cannot kill tactics. A quiet hall does not make a bad plan good, and a packed hall does not make a good plan easy. Surprise buys you time on the clock. It does not buy you the position. Mistakes are not frightening; bending down at two in the morning to pick up the tape again is what makes a forecaster. I have sat like that many times. I will sit like that again this time, but I will sit with an empty notebook, because there is not a single reference game in my hands. IF YOU ARE THINKING OF BUYING Three questions before you pay. One: does this set cover only the 9.b4 branch or the whole King's Indian system after 7...Nc6. Two: how many reference games are included, and how many of them were played above 2600. Three: does it handle White's 9.Ne1, 9.Nd2 and 9.Bg5 alternatives. If all three answers are clear, it is a decent product. If all three are vague, you are buying a handsome title. A VERIFIABLE PREDICTION If you are a club player and you buy this set for the 2026 to 2027 season, here is a prediction you can check. Over the next twelve months, you will win more games in which your opponent has not prepared for 9...a5, and lose more games in which they have. That gap will come from a single source: the quality of your understanding of the structure, not the number of variations you remember. And if you are a professional, skip the product and keep 9...Nh5. Ten years standing in the middle of arguments, and the fire lit by a question in 2026 still burns. I still ask exactly the same questions: this move is stronger for whom, under what conditions, and where is the evidence. And I still have not received better answers from the sellers of openings than from the coaches I once challenged in that press room. The most memorable thing about the Mar del Plata is not a move. It is a question: do you want to win by understanding more, or by having an opponent who understands less? Both are victories. They differ only in who has to study afterwards. And in chess, the one who has to study afterwards is usually the one who paid for the DVD.