Here is Cziffra from his memoirs. I wonder if you have any thoughts on this.
How do I feel now about my musical apprenticeship? Setting out to learn the piano seriously without being able to read music cannot do any great harm. Quite the contrary: taking care of the practical rather than the theoretical helps and speeds up the flowering and development of reflexes. The learner’s growing concentration is not saturated or dispersed by having to learn other notions his brain can well do without and he is able to work with maximum efficiency to develop his reflexes, the basis of any true pianistic technique in my view.
Do not get me wrong: I am not against theory and sight reading but I do not agree with their being taught too early. Any teacher faced with a self-taught beginner who shows exceptional skill at the keyboard will not fail to appreciate the truth of this. He should allow such hands to go their own way, while keeping an eye on how their skills develop so that the player will discover the laws governing the different phases of their spontaneity for himself.
It is far better to penetrate the mysteries of sight reading once the child, through the complicity between his fingers and the keyboard, has the all-powerful feeling that his will, as expressed by his hands, is moving over conquered terrain. This method was of the greatest benefit to me. With the help of exercises and, even more, of frequent periods spent improvising, my hands apidly became autonomous. Freed from having to search for the notes on the staves and keyboard at the same time, I was able to learn the significance of those mysterious fly-specks in record time, whereas beginners are so often put off by their apparent complexity. With this method, there was no time wasted and nothing to discourage me so that I continued to progress rapidly as well as enjoy myself. I would suggest that those who pay me the compliment of considering me to be the exception which proves the rule try this method, unorthodox though it undoubtedly is. I would go as far as to affirm that in every case the progress will be astonishing even if the pupil’s skill never rises above average. In my own case, there is no doubt that the experiment was a success way above all predictions. According to my father, my achievements by the age of five, both in theory and playing, were comparable with those of a good amateur adolescent player. From then on I progressed as if by magic, in a manner beyond all understanding.