9...a5 and the Promise of Cracking the Bayonet Attack: Dissecting a King's Indian DVD

I still remember the evening I sat down to rework the Mar del Plata variation of the King's Indian on an old chess board. White placed 9.b4 — the move known as the Bayonet Attack — and I asked myself what I would play as Black. In my notebook I wrote two lines. The first line: 9...Nh5. The second line stayed empty, waiting for another idea. Years later, a DVD appeared and filled that empty line with a name: 9...a5.

I did not buy it right away. My professional habit is to read the description first, cross-check it against my own game database, and only then decide. It was the description that made me pause. It promised something very specific: to turn the Bayonet Attack from a memorization nightmare into a strategic battle with few concrete lines. That promise sounds attractive. But in chess, a promise is something to verify, not to believe immediately.

Mar del Plata: where Black willingly steps back

To understand why 9...a5 draws attention, we need to go back to the structure of the whole system. The King's Indian is a hypermodern defense: Black accepts that White occupies the center with 1.d4 and 2.c4, builds a wall of ...g6 and ...Bg7, and then counterattacks that very center with ...e5 and ...c5. Players of this system do not seek an immediately balanced position. They seek one they can survive through storms, then explode on the kingside.

The Mar del Plata is the sharpest version of that system. After 1.d4 Nf6 2.c4 g6 3.Nc3 Bg7 4.e4 d6 5.Nf3 O-O 6.Be2 e5 7.O-O Nc6 8.d5 Ne7, the position closes in the center and opens on both wings. White has queenside space thanks to c4 and e4; Black has ...f5 and ...g5 to open the kingside. This is the kind of game where both sides race to place pieces, and whoever arrives first usually wins. There is no room for hesitation.

For decades, leading grandmasters contributed to this system. But its popularity is inversely proportional to its safety. The higher the level, the lower the share of King's Indian games — not because the system is weak, but because it demands too much precise preparation. A small mistake on either wing can become a disaster. At club level, players choose the King's Indian because they want to play to win, not to draw. It is the system of those who believe in counterattack.

The Bayonet Attack and the fear named 9.b4

Around the 1980s, a new wave appeared in how White handled the Mar del Plata. Instead of playing slowly, White chose 9.b4 — the Bayonet Attack. This move pushes the b-pawn forward, grabs queenside space, and poses a difficult question: what piece will Black use to stop that expansion?

The Bayonet Attack creates no immediate threat. It creates a structure. The b4-pawn allows White to push b4-b5 to drive a knight off a central square and open lines for the rook and queenside bishop. It also slows Black's ...a5 and ...c5 plans. In the Mar del Plata, time is currency, and the Bayonet takes time away from Black on the queenside. That is why the move became a headache for a whole generation of King's Indian players.

Theory quickly responded. The main line became 9...Nh5. The knight jumps to the rim, eyeing f4 and g3, preparing ...f5 and ...g5. This is a heavy investment: Black ignores stopping b4, accepts White's expansion, but gets a direct kingside attack in return. This approach fits the King's Indian philosophy: concede the center to gain activity.

Interestingly, the Bayonet Attack is not a single invention. It is the result of a process of accumulation: many grandmasters realized that if White does not expand on the queenside, Black will have time to organize ...f5 and ...g5 comfortably. 9.b4 was born as a way for White to reclaim the initiative.

9...Nh5: the road of forced memorization

9...Nh5 has a feature that makes it both a weapon and a burden. It opens the position, forcing concrete lines to pour out. After 9...Nh5, both sides must calculate dozens of moves ahead. There is no room for intuition; there is room for memory. That is why it is the main line, and also why many lower-rated players fear it.

That fear has a real basis. When both sides know the theory, the game becomes a race to see who forgets first. King's Indian players often tell the same story: they memorize the first 20 moves, feel safe, then at move 21 the opponent plays a move they have never seen, and the whole structure collapses. 9...Nh5 does not forgive half-prepared players.

So when a product advertises that it can free players from that memorization burden, it touches the exact pain of a specific audience: players who want to play the King's Indian but do not want to turn it into a memory test.

9...a5: the promise of a strategic battle

The DVD I mentioned proposes another road. After 9.b4, Black plays 9...a5. This move directly challenges the b4-pawn and opens a structure in which Black does not need to enter a calculation race with White.

Technically, 9...a5 is not an invention. It is a branch already known in Mar del Plata theory, appearing sporadically in games. The difference lies in the packaging: the DVD does not sell it as a new move, but as another entry point — fewer lines, more strategic direction.

The idea behind 9...a5 can be summarized like this. White has just taken queenside space with b4. Black replies with ...a5, poking at the base of b4, forcing White to decide: hold the pawn, push b4-b5, or reopen the a-file. In every option, Black can shift the game from a race of moves into a positional fight. White loses the time advantage that the Bayonet normally provides.

Comparing the two roads is clear. With 9...Nh5, Black says: I know what will happen, and I am ready to memorize it. With 9...a5, Black says: I do not need to know exactly what will happen; I only need to understand the structure. One is pre-loaded knowledge, the other is thinking on the spot.

I believe in the diagram, but I believe more in the gaps between diagrams. And 9...a5, on paper, is a move into that gap. It does not try to prove White wrong; it simply refuses to play by the rules White sets.

The hidden structure: two wings and one clock

To judge 9...a5 properly, we must look at the hidden structure beneath the surface. In the Mar del Plata, both sides race on opposite wings. White pushes queenside pawns and tries to open lines; Black pushes kingside pawns and tries to open lines. Whoever opens lines first usually wins, because speed matters more than material.

The Bayonet Attack is White's way of accelerating on the queenside. 9...Nh5 is Black's way of accelerating on the kingside. 9...a5 is Black's way of slowing the race down. When Black pokes ...a5, White loses a tempo to deal with the b4-pawn, and Black gains time to organize the kingside his own way. This is not a victory; it is trading tempo for structure.

This explains why the product describes 9...a5 as "sound" and "balanced." It does not promise Black a win; it promises Black will not be dragged into the calculation spiral White wants. For many players, that promise is worth more than a winning line.

Blind spot one: the "computers do not understand" bias

The DVD description contains one sentence I read more carefully than any other. Roughly, it says that 9...Nh5 opens the position and puts computer analysis back in an important role, while 9...a5 leads to sound positions with very few concrete lines — positions computers often do not know how to handle.

This sentence is half right. The right half: 9...a5 really does lead to strategic positions where lines do not pour out linearly. The other half is a dated bias.

The description "computers often do not know how to handle" belongs to the era before neural-network engines appeared. Older deep-search engines could struggle with closed positions requiring long-term evaluation. But the current generation of engines has completely changed how they understand structure. In many King's Indian positions like this, modern engines evaluate long-term plans that the human eye struggles to grasp. The phrase "computers do not understand" is no longer a technical truth; it is a marketing argument.

That does not mean the position is worthless. It simply means the reason given to sell the product is no longer accurate as advertised. A strategic branch still has practical value, especially for club-level players. But it has value because it suits a certain type of player, not because it "beats computers."

When a product relies on an outdated bias to differentiate itself, buyers need to know what they are paying for. Are they paying for a practical structure, or for a marketing story? The line between the two is often blurred, and that is exactly the danger zone.

Blind spot two: the silence of the author

A theory DVD that catches my attention usually comes with a first question: who made it? Without an author's name, without credentials, without demonstrative games, the product is just a floating claim.

This DVD's description names no author, cites no game, and offers no engine evaluation. It says "very few concrete lines" without showing the reader a single line. It says "chances are equal" without a single number. In my work, a claim without accompanying data is an unfinished claim.

This is a problem of an entire market. Opening theory is a stable business segment in chess, but also the most easily diluted. A DVD can compile what already exists in free databases, wrap it in an attractive claim, and sell it to learners. Its real value lies in arrangement and guidance, not in the lines — which anyone can look up.

I always spend 30% of my weekly time archiving data, because I know that when a product gives me no evidence, I must find the evidence myself. With this DVD, I opened my own database, filtered games with 9...a5 in the Mar del Plata, and checked where this branch had been played, by whom, and with what result. No answer came from the product itself.

Blind spot three: when the title does not match the content

There is one detail I must mention, even though it is not part of the technical content. The document I read has a serious mismatch: its title is about a team round in Samarkand — where the strong teams all won — while the entire body is about a King's Indian DVD. Two unrelated texts, spliced into the same package.

For someone in my line of work, reading data for a living, this is no small detail. It is a warning sign about source quality. When title and content do not match, the reference value of the whole document drops. A careful reader must ask: if the beginning is wrong, how trustworthy is the rest?

I was once pushed to the margins and learned to read what others leave behind. In this case, what is left behind is the silence about a mistake — and it says a great deal about how this document was assembled. The press room has no seat for me, but tactical history always does. And tactical history taught me that a self-contradicting source should not be cited without verification.

The price of "simplicity"

The most attractive thing about 9...a5 is also the most suspicious. It promises less memorization. But chess offers no free lunch. Every Mar del Plata branch retains a certain sharpness, however strategic it appears on the surface.

The position after 9...a5 is still a King's Indian position. White still has space, still has queenside plans. Black still has to handle the kingside with ...f5 and ...g5 at some point. "Few concrete lines" does not mean "little calculation required." It only means the lines are less forced — and sometimes, less forced is harder, because the player must invent moves instead of recall them.

For players who like independent thinking, that can be a plus. For players used to relying on theory, it can be a trap. The DVD targets the first group — which fits its product positioning. It does not try to sell to everyone; it sells to a specific group of players who want to think for themselves.

But there is a bigger risk: obsolescence. A branch considered secondary, once widely advertised, will soon be reanalyzed by the White side. And in a branch as well-trodden as the Bayonet, White usually has counter-measures if prepared enough. The antidote can become a trap for the very person using it.

Obsolescence risk: when the antidote is itself countered

This is the law of every opening-theory market. A move advertised as an antidote today becomes a hunted target tomorrow. When a product tells you this branch troubles White, then at that very moment, high-level White players are quietly looking for a way to break it.

9...a5 is no exception. If it becomes popular, White will develop new ways to counter it. This is the nature of top-level chess: every idea has a life cycle, and the cycle shortens the more widely the idea is advertised.

This does not make the product useless. It only sets a correct expectation: you are buying a weapon with an expiry date, not an invariant. For club players, that expiry date may last for years, because their opponents are not every grandmaster in the world. For professional players, it may last only months.

Three questions to evaluate a theory product

So what is the right way to read a product like this? I do not judge it by what it promises, but by what it can verify. Three questions I always ask.

First: has this branch been played at a high level, and with what result? A branch has practical value only when it survives verification by strong opponents. If 9...a5 exists only in a product catalog and never appears in real games, it remains a hypothesis.

Second: who is the author, and what results do they have in this very system? Credibility in opening theory comes not from general reputation, but from specific results. Someone who has never played 9...a5 in serious games can hardly teach it convincingly.

Third: if White prepares well, how much chance does Black have left? This is the hardest question, and also the one products usually dodge. A branch is only sound when it withstands the opponent's best counterattack.

With 9...a5, the answer is not yet in. It may be a strategic branch worth learning for club players. It may also be just a repackaging of old theory under a more attractive new name. The difference between these two possibilities will emerge in the games that follow — in open tournaments, at boards where someone actually dares to play 9...a5 against a prepared opponent.

That is what I will track. Not because I am curious about a DVD, but because every theory branch that appears leaves a trace in my database. If 9...a5 survives a few months of White-side scrutiny, it deserves an entry in my notebook. If it disappears, the lesson is just as valuable — because it reminds me that not every promise of simplicity keeps its simplicity.

The person standing at the edge of the field sees the whole game, not just what is inside the goal. And in chess, the person standing outside the mainstream lines sometimes sees a path the insiders overlook. I believe in the diagram. But in this case, what deserves more belief is the silence — the silence of evidence not yet presented.

A move can be sold, but it cannot be bought with belief. It can only be confirmed by the games that follow, on a real board, against real opponents. And that is where I will be, taking notes.