Word and music studies is like translation studies in that it is meta-interpretative. You interpret a text, then interpret what the composer has done with it, producing another verbal object comparing your interpretation of text with your interpretation of the composer's interpretation of the text.
The music the filling on the sandwich, there is text before and after.
The problem is the degree of arbitrariness, because you aren't really comparing words to music, but rather your interpretation of a text to your interpretation of the composer's interpretation. Thus L. Kramer in something I was reading last night was comparing "Goethian" and "Schubertian" interpretations of a poem by Goethe. But, of course, Schubert's reading of Goethe is as Goethian as Kramer's.
I've already written of the melodramatic mode of music analysis, the anticlimactic descent into the tonic and the startling diminished chords, all that jazz. Does anyone listen to music like that? It makes a good story... What I'd like to propose is to look at cultural and idiomatic relations between musical and poetic styles.