A.2.1:11 - Rationale

The family is needed because system classification and assignment occurrence answer different questions. Direct species are needed because the participant law for a simple shift assignment differs from the law for an appointment tied to a real commission, position, or locus.

One root signature would either reject legitimate stronger assignments or hide them behind optional slots. A generic occurrence beside a stronger one would duplicate the world-side episode and make F.6 choose between competing identities. Subtyping the direct species under U.SystemRoleAssignment preserves one assignment identity and one common holder projection.

Predicate obtaining, assertion, explicit individuation, identifier assignment, evidence, and publication also answer different questions. Keeping them separate lets evidence be corrected without rewriting the occurrence and lets ordinary recognition text remain shorter than a full relation declaration.