Pullum says "But even if you ignore all the stupid stuff, the last two sentences really are genuinely ungrammatical for perfectly clear reasons." He's referring to sentences 7 and 8, which he says are ungrammatical because of punctuation. It seems to me that for Pullum, punctuation is grammar.

I guess you're right. I suppose one of us could ask him ...


Ceci n'est pas un seing.