9...a5 Against the Bayonet: An Opening DVD's Three Claims and the Empty Ledger Behind Them

For a few years now I have kept a small sheet in my laptop — a sheet of chess opening products. On the left, the ones whose description page gives at least one engine evaluation, one database game count, or one results percentage. On the right, the claims written with no number at all. The page I stopped at this week sat at zero in both columns. It says the recommended line is "objectively equal" and, in the same breath, that it is "dangerous for White." Both can be true at once; equality does not mean a position is easy to play. But between those two sentences there is not one evaluation, not one model game, not one result. Two paragraphs above sits another claim: computers cannot handle these positions.

No name. No title. No rating. No publisher. No runtime, no model-game list, no word on whether a database ships with it. What exists is a title containing the word "Olympiad" and a move: 9...a5.

I read the scoreline once and then spent the week in the ledger. What the ledger has to work with here is a question about how much a secondary reply to the Bayonet Attack is worth in the King's Indian Defence Mar del Plata — and a larger question about why a product whose entire sales argument should rest on numbers is selling without them.

The King's Indian Defence is the opening where Black steps back twice and then hits the centre — 1.d4 Nf6 2.c4 g6 3.Nc3 Bg7 4.e4 d6 5.Nf3 0-0 6.Be2 e5. On move seven Black plays 7...Nc6 and the Mar del Plata begins, the ECO E97–E99 band. This is the branch where Black rolls ...f5-f4 at the kingside and White eats ground on the queenside, both sides attacking, both sides inside closed structures, long plans in the middle.

White's modern weapon there is 9.b4, the Bayonet Attack: a queenside pawn push, the b-file opened, a blunt instrument against Black's kingside storm. It has ruined a great many comfortable afternoons for Black, because it offers White a route of structure and understanding rather than memorisation.

Black's main answer is 9...Nh5, which the product description itself concedes is "Black's main move." It puts the knight on the rim, prepares ...f5 and ...Nf4, and is the most heavily audited line in the system. Against that, the product proposes 9...a5 — a secondary, less-played move whose whole pitch is the promise of strategy over tactics: fewer concrete lines, less to memorise, more to understand.

The product sits inside the "Svitlana" series, with "Olympiad" attached to the title. The Olympiad is biennial, fields roughly 180 to 190 national teams, and gathers a large share of the world's top-100 players under one roof. For opening material it is the cheapest, densest source available: games are public, the brand carries prestige, and nobody has to buy a scorebook.

One small thing deserves recording early, because it affects the product's discoverability. The title says "King's Indian Attack." The moves described are the King's Indian Defence. The King's Indian Attack is a different system entirely — 1.Nf3, 2.g3, 3.Bg2, d3 — with no relation to the Mar del Plata. In a search-driven market that is not just loose wording; it invites the wrong buyer in and may leave the right one, the King's Indian Defence player, outside.

Now open the argument woven into the description, because it is internally clean, and that is precisely why it works. Step one: the Mar del Plata produces mutual attacks and long-term strategic positions. Step two: computers are weak there. Step three: therefore the human-oriented player benefits. Step four: but the fashionable Bayonet disrupts that comfort. Step five: and the main line 9...Nh5 collapses back into forced, computer-friendly lines. Step six: so take 9...a5 and stay in the human domain.

The six-step chain is coherent, and that coherence is what makes it a good sales argument. The problem is that its weakest link is step two, and that link has aged. "Computers don't understand closed, strategic positions" belongs to the 2026–2026 era, when engines counted material and misjudged locked structures. After 2026, NNUE evaluation — neural-network evaluation — became standard, and it is markedly better in exactly these half-closed, slow-plan positions. Today's engine can tell you which waiting move turns into an advantage ten moves later. Selling the old heuristic is not a crime; repeating it unexamined, in a product whose only promise is that heuristic, is weak work.

Sharper still: the description contradicts itself inside one paragraph. One line says computers cannot handle these positions. A few lines later it says that after 9...Nh5 "computer analysis becomes important again." The second sentence quietly accepts the first: engine mastery is the norm, and 9...a5 is the escape from it. The real claim, then, is not that computers are weak; it is that this line offers fewer concrete engine-approved paths. That second claim is far more honest and far less exciting. Marketing kept the exciting one.

The product's scope is one branch of a tree, not the tree — and that is the first thing a buyer feels after paying. In the Mar del Plata, White retains fully independent routes at move nine, 9.Ne1 and 9.Nd2, plus earlier deviations at move eight such as 8.Be3 and 8.Re1. A Black player who adopts the Mar del Plata needs answers to all of them. This DVD, as described, answers 9.b4 alone. That is not a flaw in the product; it is a normal limit. The problem comes when "the antidote to the Bayonet" is read as "a Mar del Plata repertoire." A repertoire means a prepared answer to every plausible opponent choice. One branch is not that definition.

Using Olympiad games as model material is sensible on its face: deep fields, high stakes, public scores. It carries a selection bias that description pages rarely mention. Olympiad classical games are team matches, and in a team match a draw is often enough. When a board is playing for a team draw, play turns result-oriented and lower-risk. Opening material built mainly from such games can lack the sharpness you find in a Candidates or a pure round-robin. Learning from the Olympiad is fine; pricing a line's value on Olympiad games alone is incomplete.

Then the person who taught it. No title, no rating, no indication of whether the presenter has ever played 9...a5 in a serious classical game. For a repertoire product that is a standard credibility gap. And the data a buyer actually needs is not the author's rating anyway — it is the line's engine evaluation and its practical results. Both sides of the ledger are missing: supply and demand.

The one thing the description does well is identify its reader. "Players who think for themselves rather than memorise" is not just a marketing line; it is a real segment. Such players exist, they want structure rather than a night of line-cramming, and the market serves them poorly. What sells best is the complete King's Indian repertoire — dozens of branches, hundreds of videos, a scope that eats an amateur's entire winter. A narrow, explanatory unit has its own logic. Logic, not evidence.

The structural threat comes from format, not theory. Static media — a DVD, a video recorded once — ages fast against a moving engine world. The market is subscription-based, database-linked, continuously updated. A line-specific product has a short relevance half-life, because the moment a White analyst publishes a clean plan against it, the core promise weakens. A published antidote cannot stop itself from becoming a target.

In the Indian context this argument sits somewhere slightly different. There is a large cohort of juniors and club players here who learn openings from online material and who do not have regular access to a personal coach. For them the question is not whether 9...a5 is theoretically sound; it is whether buying one branch's answer leads them to treat their preparation as complete. The school-based pipeline and club lineage around Chennai has worked, as far as I can see, on long-term guidance rather than cheap narrow material. That is my observation, not a number, and I will not dress it as one.

Now the turn where I distrust my own habit. My image includes finding the reversal, and a reversal is easy here: declare that this small product is really a large signal. I will not, because the count does not support it. This is a low-stakes, technically plausible, narrow product selling into a niche. That is the plain reading, and here the plain reading holds. Not every piece needs a surprise; sometimes the honest answer is that the thing is smaller than it looks.

One reversal survives, and it lives in the promise rather than the theory. The product says: fewer concrete lines, therefore less calculation. In practice it runs the other way. Positions with no forcing sequence demand a decision on every move — which piece, where, when to wait, when to break. Weak players bleed most in exactly those positions, because memory does not carry them and the clock is standing behind them. The description itself concedes that these positions require long-term planning and tactical sharpness — more demand, not less. A buyer arriving for an easy line will meet a hard one and be disappointed. That is not a theoretical fault; it is expectation management, and it is the most under-priced risk in the whole file.

An old habit returns here. I built the graphic showing Spain's 1,114 passes against Russia, and it became the most-shared thing I made that summer and the most misread. After that I wrote a "where this fails" paragraph into everything. Here it is: 9...a5 works best against a White player who memorised 9...Nh5 lines and does not see the board he prepared for. The day White prepares against 9...a5, the line stops being "less concrete" and becomes simply another line both sides know.

Nobody asked for these numbers, so I archived them properly. That habit paid in 2026, when the FIDE Online Olympiad final broke at the server and India and Russia were declared joint winners. I had logged clock entries and disconnect times across six boards, so I owned the file that explained where the result came apart. Since then I build the dataset first and form opinions months later. Which is why my view of this DVD is not about the theory but about the file: the file is empty.

And the file keeps counting after the product leaves the market. Older editions in this series show the same pattern — the claims hold steady and the numbers never arrive. That is not one publisher's fault; it is the category's habit. It still needs to be called a habit.

So what to watch? Three signals. First, current NNUE evaluation of 9...a5 — if the assessment drifts clearly toward White as depth increases, the product's core claim collapses on its own. Second, the move's appearance in 2650+ classical games — one high-profile game with a good Black result renews both the line's credibility and the product's sales. Third, the frequency of 9.b4 — if White's preference shifts to 9.Ne1 or 9.Nd2, the product's addressable audience shrinks at the root.

One question remains, and it is not about the product. In a game where every move can be measured by an engine, how does a product sell without showing a single evaluation? The answer is probably that the buyer is purchasing trust, not truth — and trust is built by a voice, not a number. The day buyers ask for the scorebook instead of the voice, the first column of those pages will start filling up.