With “Stück für Stöcke,” Yann Leguay has replaced, with a piece of wood, the tablets and phones held by gamers in youtube videos. All that remains is the player’s finger gestures. The removal of the usual visual references reminds us that interfaces are of little use without our own movements. This has always been clear to the tech industry, which is obsessed with identifying every single gesture that can be patented and monetized.