I have some background in classical harmony, and now I'm reading through "The Chord Scale Theory and Jazz Harmony" by B. Nettles and R. Graf as an introduction to modern harmony. In Ch. 2 they introduce the idea of harmonic function of chords, which they divide into tonic (T - stable), subdominant (SD - unstable) and dominant (D - very unstable). They classify the I, III and VI chords as T, the II and IV as SD, the V as D (VII is context dependent).
At the end of the chapter, they suggest an analysis of the song "Killing Me Softly" for harmonic functions. I've had a go, but I have a couple of doubts, so I was wondering what other people would make of it.
Firstly, here are the chords as best as I could decipher them (transposed a semitone down):
My analysis is:
Em: I chord, T function
Am7: IV chord, SD function
D7: VII chord, D function, also secondary dominant of G.
G: III chord, T function
Em: I chord, T function
A: IV of parallel major. I am tempted to say SD function, because in the progression the next chord seems to build up even more tension. However, A is also the secondary dominant of D
D: VII chord, D function
C: VI chord, T function
G: III chord, T function? But also secondary dominant of C. I am inclined to decide T because not much feels to be happening harmonically in the C - G - C part
C: VI chord, T function
F: Phrygian II chord (aka Neopolitan), not sure of the function?
E: I chord major (Picardy third), T function