When a layer and a metric share the same label, doctrine becomes fragile. This clarification removes the confusion between EAC (the layer) and EAC-gap (the metric).
Direct references: EAC: minimum doctrinal decisions · EAC doctrine · EAC definition
The problem
In an environment where several instruments coexist (ADI-Open, ADI-IIP, IIP, Q-Layer), an acronym can slide from one use to another: sometimes a governance mechanism, sometimes a number. That slippage is enough to destabilize an entire doctrine, because it encourages optimization of a number rather than application of a framework.
The canonical distinction
1) EAC (layer)
External Authority Control (EAC) is a governance layer. It declares which external authorities may be regarded as canonically admissible in interpretive reconstruction, and under what conditions they may constrain interpretation.
2) EAC-gap (metric)
EAC-gap is a measured differential. It is expressed as an observed gap between two regimes: an “open-world” regime and an “opposable / constrained” regime. It helps diagnose a deficit of admissibility or canonization, but it is not, in itself, a form of governance.
EAC = layer · EAC-gap = differential.
Any metric use that omits “gap” is treated as ambiguous.
Why this is non-negotiable
- A metric governs nothing. It observes. Governance, by contrast, bounds and arbitrates.
- Optimizing a gap can hide an authority problem. Reducing a number without qualifying external authority produces apparent stability, not interpretive stability.
- Confusion destroys traceability. It becomes impossible to know whether a decision is normative (EAC) or descriptive (EAC-gap).
Direct consequence for the stack
The EAC layer intervenes before governed negation and before the Q-Layer output decision. The EAC-gap metric, by contrast, is read at the diagnostic level, to understand the gap between what exists and what is admissible.
