dampingwire wrote:
Unless any particular descriptivist grammar book happens to state "anything not in this book is fine too" then you'll find any given person failing to match that book too, unless the grammar was built around that person and their speech patterns remain constant.
Generally, that's how descriptivist grammars work. They say "This is the grammar of Y as it's spoken in X dialect region," with no implications that it's the only way to speak Y; they're just describing how it's spoken in one particular area, and not telling anyone that it's the only "correct" way to speak it. They don't prescribe it as correct, just describe what is actually used.