An edit is only sonically effective if its diff touched a sound-producing token, not just a comment or whitespace

The true test of whether the last edit changed the sound — comparing the FFT signature before and after — is [L3]-blocked. The static [NOW] proxy for it is to check whether the diff touched a sound-producing token rather than only a comment, whitespace, or an unused variable. If the edit changed no live token, it is sonically inert regardless of intent — the code changed but the audio engine received nothing new, which is the code-to-sound gap. This proxy lets the agent flag a dead edit today without hearing the result.

Examples

If a save only changed a comment line or reformatted whitespace, flag it as potentially inert: the change did not touch a token that affects the audio engine, so the sound cannot have changed.

Assessment

State the [NOW] proxy for ‘did the last edit change the sound?’ and explain why a diff that touches only a comment is sonically inert even if the intent was a real change.