Regardless of the nature of a song, you have to have completely mastered it, and decided for yourself what it's meaning is and how to best express that, before a song is ready to perform.   The trick is that, regardless of how a song effects you personally, you have to find the way that evokes the emotions that you want it to evoke from your audience.

We've all missed a punchline, on one ocassion or another, because the joke teller was so amused by the story that he couldn't get it out properly. A sad song, sung with an inappropriately cheerful attitude becomes amusing. And we all have seen how asinine a person can look, in both real life and art, when they overplay anger.

It is not an accident that in our great body of traditional and folk song, narrative tends to be matter of fact, rather than emotional--songs that allow the audience to infer their meaning last longer.