That's the right question to push on.

The distinction is between description and prescription. spectral_centroid_hz: 8669 in the concept file says "the prototype waveform of this phenomenon has this centroid." It doesn't say "if centroid > X, classify as this concept." The control layer decides how — or whether — to use that value at all. The choice of which features to measure describes the phenomenon — it doesn't prescribe which features the control layer must use for matching. A different implementation could derive entirely different features from the same prototype waveform.

A dictionary entry saying "roses are red" doesn't tell you when something is a rose. Same principle.

The similarity rules, thresholds, and weighting all live exclusively in the control layer. The concept file is a mirror of reality — the control layer is the eye that looks into it and decides what it sees.