Safe cases (all good):• "blank", "cat", "stop", "milk", "help" — word-final stop followed by silence or end of utterance. No aspiration token exists. Breathiness injects cleanly. ✓• "crisp", "act", "fact", "craft" — final stop in a coda cluster. Only the LAST stop (/p/ in crisp, /t/ in act) is word-final. Earlier stops in the cluster aren't. ✓• "blanket", "stopping" — stops before vowels within a word. NOT word-final. Rules don't fire. ✓• "grab", "bad", "dog" — voiced stops. Rules list only [p, t, k]. No match. ✓• "match", "watch" — /tʃ/ is a single affricate token, not "t". No match. ✓• "lapse", "box", "tax" — /p/ and /k/ are before /s/ within the word, NOT word-final. /s/ is word-final but isn't in our rule's phoneme list. ✓The problem case: "back up", "stop it"Well fuck.