As a pianist and an electronic musician, I never have any qualms about making music I can't play.

This, however, is just ridiculous.

The thing is, it's not at all hard to write a piano piece that's unplayable. Simply add a third note group far enough above or below the existing two note groups and it will be physically impossible to play (unless someone else helps you). It doesn't need to be a grotesque fountain of millions of notes to be unplayable. This is better examined not as impossible music, but as an experiment that asks the question "how many notes can you use at the same time and still make a coherent song?"

The debate between music that's playable and music that's impossible would be better served by more realistic examples, instead of a small sub-culture.