gavin bryars plays satie's "vexations"

This is Gavin Bryars' turn at the bench for the Tate Modern's 18 hour presentation of Satie's "Vexations". Satie's instructions were to play the one sheet of manuscript figure 840 times, presumably as an meditative exercise. However the piece was discovered by John Cage after Satie's death, and since then it has been performed very rarely in its entirety. It is a deceptively simple piece yet its dissonant counterpoint nature makes it hard for the player to memorize, perhaps deliberately on Satie's part.