The authors of "Phrase-final prepositions in Quebec French: An empirical study of contact, code-switching and resistance to convergence", Poplack, Zentz & Dion (2011, this issue), henceforth cited as PZD, make a strong case for showing that, in spite of surface similarities, preposition stranding in Canadian French relative clauses cannot be qualified as a case of grammatical convergence due to language contact with English, but that it rather turns out to be a result of analogical extension of a native French strategy, preposition orphaning, to a new context. The application of a particularly sound and accountable methodology, the comparative method of variationist sociolinguistics (Poplack & Meechan, 1998; Tagliamonte, 2002), allows them to invalidate the hypothesis of a causal relationship between contact and the phenomenon under study.