This is an intriguing proposal. In my experience, however, Hatsune Miku's pronunciation is not clearly intelligible upon first hearing one of her songs. The words become distinct only when I read along with the romanized lyrics. With repeated exposure to the same song, I am eventually able to understand it without the lyrics; however, I would argue that this reflects top-down prediction grounded in memory rather than any increase in the clarity of the sound itself. This is analogous to the phenomenon of sine-wave speech, in which sounds initially perceived as meaningless whistles or electronic tones are suddenly heard as clear, intelligible speech once the listener has been shown what is being said.