I agree with you Andy, but i think emotion sometimes is independent of the lyrics.

It doesn't matter too much what you said when music speaks for you.

Let's take a look at one of greatest rock hits of all time: Deep Purple's Smoke on The Water. Have a catchy hook, a great melody and a well constructed structure (conversational in the verse, emotional in the chorus).

Have you ever thought about the lyrics? Ok, its fun, but stupid at the same time. Is not a common story for most people, it´s something singullar. Does not evoque any particular emotion, like happiness, sadness, anger, etc.

I think in this case, like in many others hit songs, emotion occurs more by the riff than anything else. It´s an energic, catchy, memorable riff.

Something to think about...