This idea is really not so unusual – classical forms of composition had strict rules within which the composer would create – but in contemporary pop music I’m not sure how common this thinking is.
I was looking at 17th century architecture today in Amsterdam when this idea struck me – if one is stuck composing using one paradigm, it pays to think in different terms to generate new ideas. I like this one, because it implies thinking about structure before motifs or themes are explored.
You could even reverse engineer another piece of music in this way. I’m thinking beyond the obvious intro-verse-chorus type structure, actually incorporating macro-dynamics into the picture, e.g. Where does this composition build in intensity? What is the overall arch of the thing? Does it change dynamically, and if so, how and where?
I almost always composed from musical ideas first, most often chord changes, but sometimes from melody or rhythm. Once I had these themes in place, then I would begin to construct the music around them. This, of course, illustrates how my mind naturally works – for me, the music had to be interesting first, then everything else came from that.
But every style works differently – with rap/hip-hop, I’m guessing either the beat or the vocal comes first. With metal, it’s going to be the guitar riffs, with jazz, it’s chord changes/melody/structure.
It might be fun trying to compose something this way…