I have to say, with no offense meant, but rather as constructive criticism, that the preface is fairly pretentious considering the four method you mention have already been taught to me by my teacher. You make use of math but the math is only true if the conclusion you come to using the math is correct (In other words, you are begging the question). And usually, the author doesn't present his own work as revolutionary.
But pretentious doesn't have to be bad if you don't let us down. Like Famous literary figures like Ralph Waldo Emerson: cocky but smart. I will read the whole book and probably learn some new stuff, so I'm looking forward to it

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Oh and this: "Nobody is born with perfect pitch, because it is a 100% learned skill (the exact frequencies of the musical scales are arbitrary human concoctions -- there is no natural law that says that middle A should be 440 Hz)."
Isn't that like saying "Everybody is born color-blind, because seeing colors is a 100% learned skill (color names are human concoctions - there is no natural law that says blue is that color)"
Perfect pitch is the ability to reckognize frequencies, not notes. Later in life you learn that certain frequencies correspond to notes, but the ability to discern the frequencies is something you are born with. You can only acquire relative pitch, which maybe was what you were reffering to.