I see what you're saying, but musical notation isn't a precise representation of the audio. Given the same score, two musicians can produce very different interpretations. Perhaps I should have said 'audio' instead of 'song'. (I took classical piano exams as a kid, and at some point a group of us would perform our prepared pieces for each other as practice, and I remember always being surprised at how different everyone's pieces sounded. I'd thought mine was the One True Way!)