Repetition is over-rated as a learning device, especially on the piano.
The instrument is by definition incapable of allowing repetition--that is, if you include the strings as part of the definition. The trouble is that all too often children learn to play as if the strings had nothing to do with it.
In the fifth grade at Ravenswood Elementary in Chicago we were all given cardboard keyboards on which to "practice." A pretty good idea, actually, since sound had nothing to do with it. My very wise adult teacher, Hans Neumann, used to suggest doing finger exercises on the opposite forearm, or on the thigh--what a great idea, given the instant biofeedback re touch.
But as soon as sound enters into the picture there is constant variability: the instrument always was incapable of acoustical repetition.
Perhaps that explains the importance of the old concept of rhetoric: finding alternative ways of saying the "same" thing.
