There are no composers in old korean music. The master-players got their pieces from their masters and they handed it over to their students. Every generation changed the music smoothly and added some new parts. They call it "to wove a piece". That means, that on a Sanjo (a solo music form for korean instruments) had been working a lot of people and the roots are reaching back several hundred years. A Sanjo is extraordinarily difficult, but the fingers are moving organically - it's perfectly woven music for the certain instrument and no uncomfortable or even impossible things are in it - if you practice enough.
Many pieces in new music you can practice your whole life and it won't get comfortable - then it is something wrong with that music. For sure not woven music...
