That's exactly what I find myself doing, but:
I don't like paper
As things change I find myself rewriting the same stuff over and over
It feels like it should be easier/more effective if automated
Then again, my nestgrid project http://www.nestgrid.org (the desktop version) is IMHO, among other things. the future of this sort of notes taking but I have not yet gotten around to using it "in production".