A Night Unlike Any Other: Bayonets, Darkness and the Move 9...a5

Night falls slowly in Saint Petersburg. At two in the morning, fog creeps up from the Neva onto the window frame, and on my desk lies an opening DVD titled “A night unlike any other”. The name evokes a bayonet raid in the dark. It says nothing about a chess move. It sells a feeling.

The cover promises a Black repertoire: few lines to memorise, light on memory, meant for players who prefer to think for themselves. Amid all of that, a single move stands as the pillar: 9...a5. A rook pawn advancing one square.

I read the move three times. Then I poured more tea, sat still, and recognised I was doing my job — looking for the number behind a promise. That night, in that thick file, there was not one number.

The position belongs to one of the oldest systems of modern chess: the King’s Indian Defence. The familiar sequence: 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.

Black has conceded the centre in exchange for a solid structure and a clear plan on the kingside: ...f5, ...f4, then ...g5-g4. White has space on the queenside, and White’s plan is b4-b5, c4-c5. This is the Mar del Plata Variation, named after the tournament held in Mar del Plata, Argentina, in 2026, where the system was first played at heavy density and entered the standard theoretical canon, according to standard opening reference works.

White’s 9.b4 is the Bayonet Attack. Since the 1990s it has been one of the most uncomfortable tests for Black: White parks the centre briefly to open the queenside first, forcing Black to prove the attack arrives in time. Garry Kasparov was one of the players who made the King’s Indian a strategic weapon in world championship matches; 9.b4 became the tool of the White side that wanted to break that attack’s rhythm.

Black’s orthodox answer is 9...Nh5 — a forcing move leading into a forest of sharp variations that modern engines have analysed to the very end.

The DVD proposes the opposite: 9...a5.

After 9.b4, White has just opened a blade on the queenside. The move 9...a5 strikes directly at the b4 pawn, forcing White to define the structure before completing the plan. White has two broad choices. One is 10.bxa5, opening the a-file, allowing Black to bring a rook to a5 and turn the queenside into a two-way battlefield. The other is 10.b5, closing the queenside, pushing White to time c5 correctly, and handing Black a fixed target plus a free hand on the kingside.

Both branches steer the game toward static positions where the plan matters more than the precise sequence. That is the product’s selling point, and it is the point I want to examine most closely.

The real value of 9...a5 lies in the asymmetry it creates in preparation, not in any claim that it is stronger than 9...Nh5. This is an established alternative, a legitimate minority sideline, not a discovery. The author himself concedes that objectively the chances are equal. When a product calls itself an antidote while admitting the position is balanced, what it really sells is surprise — White sat down with a different map, and Black walked in one stretch of preparation ahead.

The central claim of the material — that computers often do not know how to handle complex strategic positions — is dated against the engine landscape after 2026. In late 2026 DeepMind’s AlphaZero won its match series against Stockfish, as published by DeepMind; in September 2026 Stockfish integrated an NNUE neural network in version 12. New-generation engines evaluate closed, manoeuvring positions with far greater reliability than the engines of the era in which the “computers cannot handle closed positions” argument was born. The slogan was once true. It is no longer true in the way it is being used to sell.

More striking is the claim of “very few concrete lines”. This is the highest-value and least verifiable promise. A Black repertoire built on 9...a5 still needs at least two legs: first, fallbacks for White’s alternatives to 9.b4 — 9.Ne1, 9.Nd2, 9.Bg5 and similar; second, knowledge of the main line 9...Nh5, because White can steer the game back to familiar structures after 9...a5. The buyer is not allowed to forget the main line; the buyer is only allowed to hope it will not be needed.

The product’s scope is also undefined. Does the DVD cover only the 9.b4 branch, or the whole King’s Indian complex after 7...Nc6? That materially changes the buyer’s preparation cost, and its absence is a gap, not a minor detail.

On positioning, the invitation to players who “like to think for themselves” targets the club and improving-player market. Elite players cannot abandon forcing main lines for aesthetic reasons. At that level, antidotes do not exist; only the allocation of preparation time does.

Based on my experience watching games at open and team events, positions like this are not won by the best move. They are won by making the opponent burn clock in a structure he has never met in his training room. Back in 2026, when I was still playing and organising tournaments, I watched a nationally ranked player lose to a weaker opponent simply because he had no plan for a closed queenside. Skill does not save a player who lacks a map.

The move 9...a5 is not a bridge. It is a footpath. And a footpath is only useful to someone who already knows the destination.

There is a collective blind spot in the way we tell chess stories: we still love the image of a human gliding through a closed position while the computer stands outside, lost. That is the memory of a closed era. Modern engines are not lost in such positions; they simply assess them as equal, and equality is a conclusion, not a confusion.

The second blind spot belongs to the trade. The title “a night unlike any other” puns on a night bayonet raid — a marketing blade, not information. The material names no player, cites no reference game, offers no database figures, no engine evaluation, no author, no publication date. The transfer market is where people sell the future to buy hope; the opening market is the same. In both, the wise buyer reads the contract before applauding.

None of that makes 9...a5 a bad move. It only places it in the right drawer: a legitimate minority sideline with practical value for those who know how to use it, packaged in advertising language larger than its substance.

For a club player who wants to cut memorisation and accept a balanced position in exchange for surprise, 9...a5 is a reasonable choice. For a player preparing for a long match, it is a reserve blade, not a system. The difference lies in whether you need to win with your opponent’s clock or with the quality of the position.

That night I closed the file and thought of the line I keep writing when the transfer window opens. A good move needs no promise at all. And when the board is full of theory, the real value lies in who still understands why they played the move.

Thirty years from now, nobody will remember this DVD cover. But if a young player learns from it how to read a structure instead of memorising a sequence, the DVD will have done its job — by a road other than the one it advertised.