An LLM as a controllable, fully-inspectable model of measurement: which features of quantum measurement are generic to bounded inference, and which are not

An autoregressive language model, read at the token-commit step, is a near-fully-inspectable classical bounded-inference substrate: the competing-route distribution over candidate tokens — the live propensity before it resolves into one committed answer — is read directly from the output logits. Used as a measurement model, it lets each structural signature of quantum measurement be tested one by one, and the genuinely-quantum residue isolated by its absence. The substrate reproduces the phenomenology of quantum measurement from classical self-conditioning — back-action, non-commutativity (order effects), entropy-collapse on commitment, a substantial Busemeyer–Wang QQ-structure (order-effect difference q not distinguishable from the parameter-free quantum value 0; pooled across eight de-saturated base models over five vendors and four architectures, N=96, q=-0. 003, 95% CI -0. 025, +0. 019), interference, einselection, an Aharonov-style weak-versus-strong asymmetry, and measurement-mode dependence — but not the quantum core: genuine contextuality is robustly absent (an analog Contextuality-by-Default cyclic-4 analysis gives CNT < 0 in every model and scenario), and no phase/coherence is demonstrated. A controllable analog Bell-loophole testbed makes each premise's price visible within one substrate (Sₐnalog ~ 2. 00 with all loopholes closed; ~ 2. 8 on opening locality or measurement-independence), and a within-substrate timeline reads the propensity resolving across network depth, including a maximally-contested case whose outcome is never created. The order-effect incompatibility is shown to be a measured, correctly-signed classical-complementarity dial that falls as the readout partition refines. Positioning. The contribution is the demarcation itself, with statistics, made possible by an inspectability no veiled (physical or psychological) substrate allows. It instantiates beim Graben it makes no claim about physical reality. Companion papers (Friction Theory series): Paper 1 — Friction as the cost of probabilistic computation (10. 5281/zenodo. 20012654) ; Paper 10 — Race all the way down/up (10. 5281/zenodo. 20014567) ; Paper 21 — LLMs as a measurement model for bounded-decision cognition (10. 5281/zenodo. 20562416) ; Paper 28 — Dread without a dreader (10. 5281/zenodo. 20690747). Paper 18 in the Friction Theory paper-series. Submitted as a careful, honestly-scoped empirical demarcation (target venue: Entropy, Quantum Information / quantum-cognition & foundations-of-measurement).