This is a common topic of conversation with my students. I think an artist -- in any field -- needs to completely understand the technical side of his or her art. Great artists make it look effortless, but that hides many, many years of practice.
Photography occupies an odd niche, since it's possible to make photographs without learning any technical stuff first. One just "pushes the button." This is different than playing the guitar, or painting a portrait, or singing an aria, or welding a metal sculpture. In all cases, though, the artist *uses* the technical skills to perform or create their art.
The problem, of course, is that for some people, the technical issues become the only issue. This isn't limited to photography, but it seems to be magnified especially with the advent of digital imaging and the "actual pixels" view in Photoshop.
So, I think your friend needs to learn a lot about photography in order to be a great photographer/artist.