Nothing. Absolutely nothing. I loved Gilles because he suggested Writing Project philosophy for improving writing instruction.
"The key is regular, informal practicer at writing." (5)
"Our service courses should provide students with the oppotunity to practice the craft of writing." (5)
And his three purposes for a liberal arts education. All good. Yes, he says that other disciplines blame composition for not teaching students how to write. Someone will always be blaming you for something. Probably rarely to your face. Just do what you know to be write. Be conscientious. Work hard. Be fair. And you will see improvement in student writing. If you make them comfortable with writing, they will succeed in other disciplines. I truly believe that.