Now apply this concept to the act of editing photographs (Whether that may take place in the darkroom or on the computer is not important right now). Does the music a photo-editor listens to while doing his job affect the outcome of the photo? Absolutely. Although the musical intonations may not be directly translated into the mood of the photograph, I firmly believe that whatever is inputted into an artist amidst the process of creating art (Or in the artist's past) will affect what he is outputting.
Consider this rather blunt example. A boy who lost a number of loved ones at a young age eventually becomes an artist. What are the chances that he will adopt a more melancholy style of art? Quite high. In this scenario, the history of an artist (The input) impacted the art he created (The output).