The Deceptiveness of Beauty theme can be applied broadly to alot of things, really. Tossing up a few things here - talking about masks and layers - hiding self, as in Keller and his [face] of music as being rigourous and hard, unemotional and a strive for perfection of control [of your hands to play the pieces, for one] and also of perfection to reveal imperfection... [Paul's technical perfection is actually imperfect]
Beauty is a deceptive mask of imperfection. Examples that can be shown is the seemingly represented beauty of Paul's performances of the piano, to hide the lack of emotion and spirit that a true virtuoso requires - you can take the example of Keller as well. You can also thrown in whats-her-face.. uh, Megan. Same thing, seems beautiful and goddess like but's quite [bleh] when Paul has sex with her.
...Ok, that was a bit of grabbing at air.