"Should I give up or should I just keep chasing pavements
Even if it leads nowhere or would it be a waste
Even if I knew my place should I leave it there
Should I give up or should I just keep chasing pavements
Even if it leads nowhere...."
Adele

I've read (not skimmed) the QES article. Mr, Geoffry Pullum repetedly associates 'grammar-ungrammatical' with punctuation and clause. Which is why I don't understand :

"agree that reading lots will help with punctuation. But that's not "grammar" as I define it. Knowledge of punctuation is a writing skill, it has nothing to do with our unconscious knowledge of how the language works, I think."