 Personally, I do not believe that there is such a thing as perfect pitch. If I understand "perfect pitch", a person can identify a predefined frequency with accuracy (i.e., 000Hz). The concept "one second" is a defined by humans (the duration of 0,000,000,000 periods of the radiation corresponding to the transition between the two hyperfine levels of the ground state of the caesium 000 atom); as I know it, there is no inherent frequency standard or reference built into humans. Who defined 000 Hz as A above middle C? Humans can't identify a legth of time "second" within one hundreth accuracy, but one can get a sense of what a second feels like. Similarly, there is more likely an ability or talent to identify when a frequency is within a range that has become familiar to the listener. Those are my two cents! 