I am not sure... . These pieces (especially the preludes which never have a "melody") are very difficult from several perspectives. One is that they reappeared in the musical repertoire only at the beginning of the XXth century, introduced by Casals. There is neither tradition nor score indication of how they should be played. Every musician does it according to his/her taste and musical understanding. Casals recorded them after he was 60. Rostropovich recorded them at 63 after having acquired the wisdom of an entire musical life. His rendition is my reference, and this performance is pretty far from that. So is Yo-Yo Ma's version which is an epitome of exaggeration.
