Josef Fruehwald (2013)
First, I look at a few cases where there is a mismatch between the predicted conditioning of phonetic change on phonetic grounds versus phonological grounds. In the examples available from the Philadelphia neighborhood corpus, it appears as if phonological conditiong is at work from the very onset of the changes, rather than being late-stage reanalyes.
Then, I look at parallel phonetic shifts, which involve the wholesale, simultaneous phonetic change of a phonological natural class.
It's a tie for my favorite figure from this chapter. First is the result of a model which shows that pre-voiceless /ay/ raising (a.k.a Canadian Raising) has always applied before flapped /t/ and /d/ in the same way as it does before unneutralized /t/ and /d/.
Second is this plot showing the diachronic trajectory of just 'day' and 'days', showing that /ey/ raising in Philadelphia is an active phonological process.