. . . . "No, if you are good at scales then you will be able to play Bach, Mozart, Chopin, Rachmaninoff, and any other composer who decides to make a piece with notes that go up or down side by side.In other words, pieces that use a part of a scale, or notes that go up and down.If you practice Bach, you will only know how to play Bach, but not very well, because Bach is not great for starting off technique" .