Why can't you develop a tune?

I really wondered about this when I was a teenager. Using the ideas of prolongation that I'm developing here, the answer is quite straightforward: a tune is a coercion of tonality as well coercion of patterns. It can be disrupted harmonically (jazz harmonies for example), or can be disrupted rhythmically (percussion, syncopation). But it's essence is its own coercion. This makes other coercions difficult, and exhortation (taking into another world) even more so (unless perhaps it's done like a passacaglia)