Greatness is not era-proof. It is era-priced.
A player's ability does not change when you move him through time. What changes is the value the game places on it. A ball-playing defender is worth far more in the build-from-the-back era than in a route-one one; a pure target man was worth more when the ball came long. The engine holds the underlying rating fixed and era-agnostic, then reads how seven documented shifts in how the game is played re-price his archetype, forward into the modern game or backward into an older one. It lays out the re-pricing and stops. It never declares which era was better.
The rating does not move through time. Its value does.
The underlying trait identity is locked and era-agnostic; the engine never touches it. It produces a separate Era-Projected KR that reads how the documented shifts in the game re-price this archetype, and reports it as a band, because an era projection is a counterfactual with no direct data. This is a composite ball-playing defender, projected forward from an older era into the modern game.
His 84 never moved; it is his ability, and ability is not era-dependent. What the engine shows is that the modern game values that ability far more than the older one did, so his Era-Projected KR lands in a 90-to-94 band, reported honestly as a model-derived counterfactual, not a fact. The projection re-prices the archetype and stops. It does not say the modern game is better, only that it pays more for this player. The player is the constant. The era is the price.
Illustrative engine read on the real era-projection structure (locked era-agnostic OVERALL, a separate model-derived Era-Projected KR band, the per-factor re-pricing). Composite player, demonstration figures.
What one era elevates, the other buries, by the same amount.
The seven shifts re-price every archetype, and the projection runs both directions: a tailwind projecting forward is a headwind of the same size projecting backward. The roles the modern game invented gain the most going forward and nearly vanish going back; the roles it squeezed lose going forward and gain the most going back. Two composite players, opposite archetypes.
The magnitude is symmetric; only the sign flips with direction, because if the modern game elevated a skill, removing that modern context removes the elevation. This is the death-of-the-number-10 case made precise: the free central creator and the target man read as premiums in one era and as luxuries in another, and the engine prices both without ever ranking the eras themselves. An era does not make a player better or worse. It changes what his particular gifts are worth.
Illustrative engine read on the real bidirectional archetype matrix (forward tailwind equals backward headwind of the same magnitude; modern-elevated versus older-devalued roles). Composite players, real archetype magnitudes.
You cannot claim a big era swing on a shaky archetype.
An era projection rests entirely on the archetype, and an archetype is only as trustworthy as the data tier that produced it. So the engine caps the maximum era swing by confidence: a thinly-read player cannot be swung as far as a richly-measured one, no matter what the raw factors say. When the raw net exceeds the cap, the engine clamps it and flags it.
The factors might say plus eleven, but if the archetype behind them is a reasoned guess, the engine will not spend that confidence it does not have. It clamps to the tier, flags the clamp, and reports the whole thing as a model-derived band, because an era projection is a thought experiment on one scale, not a measurement. The size of the claim can never outrun the quality of the read.
Illustrative engine read on the real confidence-gate structure (max era swing clamped by the archetype's data tier; GATE_CLAMPED flag; model-derived band). Composite player, demonstration figures.
A player's ability is a constant the engine holds fixed and never touches. What time changes is the price the game puts on that ability: the pressing revolution, the build-from-the-back era, the athleticism trend, the attacking full-back, the protection of skill all re-price each archetype, and the engine reads that re-pricing forward and backward, symmetrically, one scale across every era. It caps how far it will swing a player by how well it actually knows his archetype, and it reports the whole thing as a model-derived counterfactual, never a measurement. And it stays weightless: it lays out how the game re-prices a skill and stops, refusing to declare that any era was the better game. The player is the constant. The era is the price. That is the only honest way to read greatness across time.
Hold the player fixed. Read the price of his era.
Era Projection re-prices a locked archetype across football's documented shifts, both directions, gated by what the read can support.