Composers have been known to write in fist-clusters and forearm-strikes that resemble the sort of stuff going on in the video. Ben Folds in the early days would

Composers have been known to write in fist-clusters and forearm-strikes that resemble the sort of stuff going on in the video. Ben Folds in the early days would often slam his piano bench into the keyboard to hit quite a few more notes than would be possible using just one's arms and hands, even.