Mormon Doctrine

From this reddit thread where a person posted their facebook message feed, a believing Mormon posted:

"Oh calm down. Mormon Doctrine is not accepted as approved doctrine."

We have a person who is sustained by Church members to be a prophet, a seer and a revelator, who is part of the ultimate decision-making body of the LDS Church, who writes a book titled Mormon Doctrine. But the book is not accepted as approved doctrine. The title of the book does not describe what is in the book. The words Mormon Doctrine don't mean the doctrine that forms Mormon beliefs. The words Mormon Doctrine mean, one person's (who happens to be an apostle) personal views and opinions on Mormon doctrine.