Is the wrong question. What we should ask is, can you learn writing?
To which the answer is an unequivocal YES! All writers teach themselves, through an intense and lifelong process of reading, writing, critiquing, editing, rewriting and rereading. This is how we learn.
In this process, a good teacher can save you immense time and effort. A good teacher can show you in an hour the four main point-of-view styles that the bulk of commercial fiction is written in. I have seen students stumble for years to find what they could learn in an hour.
So if the answer is self-evident, why do we continue to ask, can you teach writing? Is the question we are really asking; is writing teaching of value? Is it, in the logic of the capitalist market system, worth a buck?
Here is one certain answer. If you are asking that question, you are not ready to learn any creative discipline yet.