E.10:6.2.2 - Plain Twin Safety constraints (normative)

CC‑TWIN‑1 - One‑to‑one and local. Each Tech designation has at most one plain twin for one stated local meaning and didactic use; that plain twin points to at most one Tech designation in the same use.

CC‑TWIN‑2 - Sense‑equivalence proof. A plain twin names the same value under the same local meaning claim and effective scheme as its Tech designation. When an F.17 SchemeSenseCell exists for that use, both expressions resolve to that exact cell. The registry notes include at least one counterexample showing how the twin could be misread and why the stated use still passes.

CC‑TWIN‑3 - Head‑term discipline (HND). The plain twin preserves the head term of the Tech name or appends an explicit bracketed head on first use:

• A Plain twin for one exact local system-role kind keeps “(system role)” and names its Tech designation on first use. Bare role is not a Plain twin for a universal kind. When service or access still hides its object or relation, follow L-SERV and A.6.P:4.11a; after recovery, keep that object’s or relation’s head. Methods keep “(method)”, U.Work as a kind keeps “(work kind)”, one Work individual keeps “(work occurrence)”, a separate episteme about it keeps “(work record)” only when its Tech name denotes that record, and Capability keeps “(capability)”. Examples: TransformerSystemRole → “Transformer (system role)”, U.PromiseContent → “post-op monitoring service promise (promise content)”; an exact access relation → “service access (access relation)”, U.Work -> work (work kind); PumpInspection_2026-07-22T0900 -> inspection work occurrence; PumpInspectionRecord_2026-07-22 -> inspection work record only when that Tech name denotes a separate episteme.

CC‑TWIN‑4 - Kind‑consistent. A plain twin does not map across Kinds (C.3). If its everyday interpretation can denote a different kind—for example, Tradition as organization, corpus, or field—it is admitted only with a bracketed head and a first-use local gloss (see CC-TWIN-7).

CC‑TWIN‑5 - Ambiguity stop‑list. The following base nouns are reserved and are not admitted as unqualified plain twins: Tradition, service, process, function, model, system, method, standard, library, dataset, evidence, activity, task, action. They are allowed only with an explicit head per CC‑TWIN‑3 and a first-use local gloss (CC-TWIN-7). (This list may be extended in the registry.)

CC‑TWIN‑6 - No cross-local relation by label. Plain twins are not portable by spelling. Reuse under another local meaning first recovers that exact value, scheme, expression, and local-sense claim. Cite an F.9 Bridge only when its direct relation between distinct exact cells actually obtains; names alone carry no authority, equivalence, or substitution.

CC‑TWIN‑7 - First‑use gloss. At first occurrence in a document or screen, show a plain twin as “Plain twin [Tech designation] — local gloss”, for example: “Transformer (system role) [TransformerSystemRole] — one local kind for systems already admitted under A.1 and eligible for the stated transformer assignments in OR_2025; classification creates neither an assignment nor Work. An assignment claim names both an A.2.1 occurrence and its declared U.SystemRoleAssignment species”.

CC-TWIN-8 - Normative and didactic placement. Use Tech names in Conformance Checklists, predicates, type signatures, and acceptance clauses. Reserve Plain twins for didactic use.

CC‑TWIN‑9 - Twin budget. At most one plain twin per Tech designation for one stated local meaning and didactic use. Synonym piles are non-conformant because they create uncontrolled vocabulary sprawl (see F.14).

CC‑TWIN‑10 - Registry entry and DRR. Every admitted plain twin has a registry entry recording tech, plain, referenceScheme, localSenseClaim, sourceOrPracticeBoundary, didacticUse, head, SenseFidelity = {3,2,1,0}, ambiguity notes, counterexamples, and DRR id. A change opens a DRR.

CC‑TWIN‑11 - Tests. Twin entries pass the Twin Harness (see F.15): Head term, Kind consistency, same value and local meaning, Stop-list compliance, and First-use gloss. When a SchemeSenseCell is current, the harness also checks the exact cell.