|Abstract:||Evolutionary Phonology suggests that, to avoid duplication in linguistic theory, diachronic explanations must take priority over synchronic explanations whenever possible. As a corollary, linguistic theories should not encode phonetic motivations for phonological patterns in a synchronic grammar. This commentary argues that there exists a synchronic phonological pattern in Japanese which is constrained by a phonetic factor. Japanese speakers prefer geminate stops to geminate fricatives when they create emphatic forms, even though both types of geminates are equally well attested with comparable lexical frequencies in the Japanese lexicon. I argue that the preference follows from a phonetically natural constraint, and that none of the canonical diachronic mechanisms provides a satisfactory account for the pattern, contrary to the central premise of Evolutionary Phonology.