I happen to think "Birth, School, Work, Death" is about Fight Club, Office Space, and Dead Like Me -- and now I think it is about The Matrix as well. Damn your brain.

Sigh.

Basically the Keanu factor is that he gives the audience exactly what they expect - there are no real surprises with him, so the audience can relax and absorb the *actual* unexpected twists and turns of the plot. He is a comforting presence amongst the strangeness much like literal interpretation/expected lyrical interpretation can help ease an audience into a difficult portion of the vid -- same principle as your "blind them with candy and then gut them like fishies" technique, but with Keanu.