A guy named Alan Pollack wrote a very nice analysis of “Dear Prudence” as part of his exhaustive music-theoretical study of the Beatles’ entire repertoire. Pollack observes that the tune shows John borrowing characteristics of George’s style — the droning pedal tone and air of melancholy. Pollack draws a parallel between “Dear Prudence,” “Rain” and “Tomorrow Never Knows.” While most Lennon tunes have an arch shape to them, “Dear Prudence” is more riff-oriented.