Loving this thread. I agree that much can be just absorbed by exposure, and that you can be a great writer without being able to explain grammar rules. I was so poorly served by my lack of a basis in English grammar, though, that it made learning a second lanuguage more difficult (Spanish), and even the third (German). I taught Spanish...but sometimes not very well because I was really bad at explaining grammar. I just know that I would have loved learning it the way dd did and I would have liked (would still like) to understand WHY something sounds right or wrong.