Phonetic variation has been considered a barrier that listeners must overcome in speech perception, but has been proved beneficial in category learning. In this paper, I show that listeners use within-speaker variation to accommodate gross categorical variation. Within the perceptual learning paradigm, listeners are exposed to p-initial words in English produced by a native speaker of French. Critically, listeners are trained on these words with either invariant or highly-variable VOTs. While a gross boundary shift is made for participants exposed to the variable VOTs, no such shift is observed after exposure to the invariant stimuli. These data suggest that increasing variation improves the mapping of perceptually mismatched stimuli. (Contains 2 tables and 2 figures.)