I’ve been thinking about this question since I occasionally teach one-day writing workshops at colleges in the area. I came upon an interesting sentence at the Iowa Workshop website. “We continue to look for the most promising talent in the country, in our conviction that writing cannot be taught but that writers can be encouraged.”
I certainly encourage the writers who attend my classes, but I also believe students can learn certain elements — narrative drive, pacing, character development, plot, to name a few. Writing is not as easy as it looks but, like anything else, practice builds skills.