9...a5 and the Bayonet Problem: Inside a King's Indian Mar del Plata Lecture DVD

A pawn advances exactly one square.

Nine...a5. In a King's Indian Mar del Plata, where the two wings hurl themselves at each other like a gunfight, spectators are trained to wait for the bang. They wait for ...Nh5, the knight leap to the rim of the board that tears open every diagonal and forces both sides to calculate move by move. And ...a5 is only a single step by a queenside pawn: quiet, almost saying nothing.

I lingered a long time over precisely that move inside a promotional file sent by a chess lecture publisher. The file ran to thousands of words, but what kept me seated was one tiny square, a5. In commentary work, the moments worth remembering usually come from places like this: a detail that looks meaningless, placed correctly, suddenly rotating an entire game around a different centre of gravity. The microphone does not make the storyteller. It is the silence of the stands that signs its name beneath every line.

The King's Indian Defence (1.d4 Nf6 2.c4 g6 ... Bg7) is the classic hypermodern system: Black concedes the centre early and comes back to seize it. The Mar del Plata variation, with ...Nc6 and ...e5, is its sharpest branch, roughly ECO E97 to E99. The two sides attack opposite wings, and whoever is slower usually loses.

Against it, White has the Bayonet Attack: 9.b4, a pawn push that grabs queenside space and forces Black to answer immediately. The orthodox reply is 9...Nh5, a leap that opens the position and forces calculation. For decades it has been treated as the main road. Garry Kasparov used the King's Indian to beat Anatoly Karpov in game 16 of the 2026 World Championship match, a game that entered history as a statement about the system's vitality at the very top.

The product I am describing is not a tournament. It is a Fritztrainer-style lecture DVD, its author unnamed, promoting 9...a5 as an antidote to the fashionable Bayonet Attack. The sales pitch is folded into one idea: change the character of the game, from the concrete, forcing, must-memorise lines after 9...Nh5 to a strategic struggle with few concrete lines after 9...a5.

One detail about source quality: the original document's headline refers to Samarkand R2 (open) and to the top teams picking up wins, a team-round report with no connection whatsoever to the content beneath it. Two different texts have been spliced together, and for anyone whose job is verification, that is a red flag.

What is worth discussing here is not the move but the way it is sold. 9...a5 is not an invention; it is a long-known branch, a second-tier alternative behind 9...Mh5. The pawn push to a5 attacks the very b4-pawn White has just advanced while steering towards a more closed game, where both sides grind along files and weak squares. The branch is real and has value, but it is not a theoretical novelty. The promotional text does not claim otherwise, admitting there are few concrete lines. What stands out is something else: the product positions itself with an argument about humans and computers.

That argument, compressed: 9...Nh5 opens the position, forces the lines, and makes computer analysis important again, while 9...a5 leads to sound positions with very few concrete lines. It sounds seductive to club players. It is also very easy to falsify. The problem lies in the underlying assumption: that a category of position exists which computers do not understand. That sentence belongs to the pre-AlphaZero era. Neural-network engines today handle long-term King's Indian positions far better than the marketing implies. When a product uses computers cannot handle this as its differentiator, the buyer should read it as a marketing strategy, not a technical truth.

The claim of very few concrete lines also deserves scepticism. The Mar del Plata is inherently sharp: Black concedes space, White piles up, and no branch truly removes calculation. Even if 9...a5 softens the theoretical intensity for a few moves, the game still demands that the Black player understand the structure, know when to open the kingside and when to keep it shut. That is not no studying; that is studying a different way.

The file offers no sample game at all. No win rate, no move-quality metric, no engine evaluation, no author name. For a product sold on a technical argument, that absence matters more than any promotional sentence.

Across more than thirteen years of following chess, I keep one habit: before trusting a move, I open three windows - the database, the analysis board, and the notebook where I write down what I feel. If a move exists only in the third window, it is inspiration, not theory. 9...a5 exists in the first. But the story the product tells around it lives only in the third.

The contrarian angle here is not the move is bad. It is something else: what is being sold is a feeling of safety. An antidote to a fashionable opening line is the best-selling genre in the theory market, and also the fastest to expire. The moment 9...a5 spreads among Black players, White will respond. Theory is a cycle: antidotes breed counter-antidotes, and in a branch as thoroughly ploughed as the Bayonet, the golden window of any secret weapon is shorter than buyers imagine.

More subtly: the sentence if Black knows what to do, things can quickly become dangerous for White is true in an unfalsifiable direction. It depends entirely on the opponent's level of preparation, which nobody can measure. Sentences like that are not analysis; they are belief packaged as forecast. And when the easiest part of a document to check, its headline, is wrong, how much credit does the hardest part deserve?

Fairness is required too. A strategic, accessible approach, aimed at players who prefer thinking for themselves over memorising, is a genuine market segment. Plenty of club players hate forced twenty-move lines. For them, a less theoretical branch, even if not objectively stronger, is still useful. The problem is only that the product promises more than it proves.

Sport does not promise victory; it promises only a heartbeat willing to continue. Chess is the same. No ninth move, whether ...Nh5 or ...a5, promises anyone an easy game. The only thing a move can promise is a different conversation with the opponent.

Sports culture is a graveyard of names, kept alive so their stories can last one more inning. In that graveyard, the moves that live longest are not the loudest advertised, but the ones that survive the silence after every pitch has faded. The question I leave behind is simple: if tomorrow you sit down at the board and meet 9...a5, will you trust the flyer or trust yourself?