The site doesn't tell you what you think. You already know what your own beliefs are. Having said that, after going through the questions on that site, people are often suprised at where they land on the graph, and with whom they share beliefs. (I believe this is often because people mislabel themselves, and/or associate themselves with what or who they think is "cool" in popular culture...but I digress).
The goal of the site seems to be to promote the idea of a more descriptive way of succinctly identifying your political leanings to others, rather than using the traditional "left" and "right" labels. I often refer to the site to show my basic political beliefs rather than saying that I'm "left" or "right", or "liberal" or "conservative". I think it's an interesting idea myself.
As for the lyrics, I never liked the idea of everyone having their own personal interpretation of lyrics. If a song has a different meaning for everyone, then what's the point really ? Lyrics should mean something, and express the beliefs of the author, or whoever the speaker/character in the song is. It's great if they promote thought, debate, introspection, etc, of the ideas expressed in the lyrics, but not of the meaning of the lyrics themselves.
I've never really enjoyed lyrics that were so nebulous that they could mean anything, or so obscure and/or personal that they are completely inscrutable to anyone but the author. This is probably why the focus of my enjoyment of music has always been with the music itself, not neccessarily the lyrics. The vocals are just another instrument to me. The lyrics themselves are more like a bit of frosting on the cake, if they're meaningful. Of course, I recognize the fact the lyrics can be meaningful to one person, but perhaps not another because of their experiences, whether the lyrics were interpreted correctly or not.
Just my opinion
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