I can not comment on the rate. But ear tuning is a lengthy self generating process. No one can guarantee that he can tune some students ear, the tutor can help a bit only. To make it happen the only solution is the student has to listen songs and music as much as possible, more time is required for listening than learning of any instrument be it guitar, keyboard etc. it is said 70% listening & 30% practical learning process. Once you learn the basics and comfortable in playing chord progression, musical notations clearly, then try to play any song by hearing it. Gradually you would learn on your own and ear will be tuned as well in due course of time. I can say that ear tuning is completed only when you are in a position to write the complete notation, chord progression, bass line etc. of any songs by simply listening to it. Its absolutely my view from experience. Cheers