Three findings from DIFFERENT substrate classes converge on single-entity-dominance. Hypothesis: substrate-class-INVARIANT property (SED-default) — every substrate >N=1 trends toward single-entity-dominance unless an anti-collapse mechanism is engineered.
EXPLICIT SCOPE RESTRICTION: NOT a SAS-vs-MAS reasoning claim. Substantively distinct: substrate-default-collapse-shape, NOT compute-accounting bound.
Pre-registered threshold: modal-entity-dominance-share ≥ 70% per cell, ≥4/5 cells agree on classification under ≥2/3 operationalizations → CONFIRMED.