Frequency-aware latency estimators let deadline-aware DVFS governors schedule edge ML inference by modeling latency over CPU and GPU clocks, but they cannot observe the memory clock (EMC) -- a missing deployment state that decides whether a governor meets its deadlines and at what energy. We show this with a deployed, measured governor on a Jetson Orin NX: an EMC-blind GPU-only fit misses 25-28% of cycles at tight deadlines, whereas an EMC-aware refit holds misses to at most 1.3% under a 2% QoS miss budget by selecting a budget-feasible clock -- the energy-minimal one for periodic vision (calibrated module-rail power). The failure generalizes across three workload classes -- MobileNetV2, a ViT transformer, and Qwen2.5 LLM token decode (where saturated decode makes the aware policy lower-energy than the infeasible blind choice): a CPUxGPU estimator sends the deployed governor to an infeasible operating point, and only an EMC-aware model identifies the feasible side of the energy frontier. The effect is real and outside the CPUxGPU state abstraction: across two Orin SKUs sharing the same lockable EMC points it shifts median latency by up to ~45%, replicates on both, and survives a fused TensorRT fp16 engine. CPUxGPU models do not absorb it: per-lockable-point EMC tables are needed, a scoped inversion shows monotone assumptions can pick the wrong direction, and clustered misses make aggregate QoS rates understate deployment risk. We release the harness; this complements, not rebuts, the state of the art within its CPUxGPU scope.
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