Also I don't think of grammar as something one 'uses'. It's an inner annotator that works along subconciously when one writes something. But once it was explained and conciously studied.
What was explained and consciously studied was just a very small subset of English grammar, namely the parts that there was disagreement about. This teaching started in the 1700s, I think. Before that, English grammar in any form was not taught. So how did those great writers of the 1000s-1600s manage to write?
Barzun says
The loss of grammar and the dogma that anything said is to be treated with respect due to life itself have had the further cultural effect of encouraging the natural carelessness of talk; it even made it an asset: a new president of the United States in 1988 gained in popularity when he was found halting in speech and loose in grammar.
He would have to show exactly what he means by "careless", and that talk now is more careless now than it was in the past, and more careless now than it needs to be.
