Coherence Before Information: Admissibility Constraints on Fine-Tuning, Simulation, and Informational Ontology (IM-D004, v0.3)

This document is part of the Informational Mechanics (IM) framework and is published in the IM-D (Core Physics) series within the IM v0.3 corpus. The paper derives conservative theoretical consequences that follow once scientific discipline—formalized in IM-C002—is strictly enforced prior to explanation. Rather than proposing new axioms or mechanisms, it applies admissibility, persistence, and operator-defined observability constraints to analyze why several widely discussed explanatory strategies recur in modern physics. Apparent fine-tuning for life or intelligence, simulation-based explanations, cyclic cosmologies, ensemble selection, and information-first ontology are treated not as competing answers, but as instances of a common structural overreach: presupposing scientific discourse in regimes that cannot support stable structure, measurement, or comparison. The analysis provides a structural classification of fine-tuning explanations and shows how each class exceeds the admissible domain of scientific explanation under Informational Mechanics. These exclusions are classificatory rather than polemical: the frameworks are not refuted, but shown to be non-scientific once testability and observability are strictly enforced. The paper states explicit, falsifiable consequences whose evaluation is deferred to a companion experiments and simulations paper (IM-G001). No experimental results are presented here. The purpose of the work is to restore classical scientific discipline by clarifying which explanatory strategies remain meaningful once admissibility comes first.