Of course it has. It's the basis for most of the alternative notation systems. The shape note systems of Sacred Harp are based on moveable do, for instance, and

Of course it has. It's the basis for most of the alternative notation systems. The shape note systems of Sacred Harp are based on moveable do, for instance, and they were very successful in promoting music literacy in their culture for a good 100 years. Chinese notation is also moveable do. So is Roverud's cipher notation which I mentioned above (I think it has a common root with the Chinese one). So is the Kodály method. All these systems have been really successful in teaching where they were applied, but they always fall for the push to graduate to the "real" notation system.