If I try to do a harmonic analysis of a song, and try to find which key a (part of a) song is, I fail a lot. I try to listen which chord feels like 'home', but that is not so clear to me...
Example: Tee Set - Ma Belle Amie, the verse. Chords:
D7 - G - G - Em - A - D
The two options that I can not choose between are G major and D major. In G major, this would be: V7 - I - I - vi - V/V - V In D major, this would be: I7 - IV - IV - ii - V - I
If I ignore what my ears tell me: it starts and ends with a D, which makes me think it is in D, but the bridge is clearly in G, and I don't feel a key change, so that makes me think it is in G. My ears feel at home on the second chord (G), but also on the last chord (D). I tried to analyze songs before by myself, and then look how other people analyzed these songs; sometimes I guess correctly, sometimes I guess wrong, but my guesses are not getting better.
My question is not what the key of this song is, but my question is which approach should I take to find the key of this song, when the common advice of 'listen which chord feels like home' does not work for me.