Saussure's Prescriptivism

The last two quotes Derrida provides in "The Inside and the Outside" won me over to his side a bit. These are the ones where Saussure complains about the way the writing system is damaging the pronunciation of French, splitting the surname Lefèvre into Lefèvre and Lefèbvre and leading people to pronounce the last two letters of vingt. Saussure depicts this as a decline from pre-existing correct system of French pronunciation, instead of just another instance of language evolution. Any contemporary linguist will tell you that there is no "correct" pronunciation of a language beyond whatever the current consensus among its speakers calls correct, and that consensus is always changing. (Remember that French is nothing but the noble Latin of the Roman emperors after a thousand years of abuse in the mouths of a bunch of Gallic barbarians.) By assuming that there is some objective standard of correctness (which, I'll bet you dollars to donuts, just happens to coincide with the way Saussure says Lefèvre and vingt) Saussure in engaging in what linguists call prescriptivism, which is a mistake when you're trying to be empirical. Furthermore, the excerpts make it clear that this isn't just a matter of tone, but a well-definied assertion. When Derrida shrugs at this and says "Where is the evil?" he's doing exactly what I would do in front of a Linguistics 101 class.

From a modern linguist's perspective it seems odd that Derrida would treat Saussure's prescriptivism as one element in a larger defense of writing, rather than seeing the business about writing as just one aspect of pernicious prescriptivism, but whatever. Derrida's interest is writing here, and it does appear that Saussure focused on writing as well.