Amaxing

So what is the Secret to her DDR super Gloomy Puppet Show? I searched the internet but theres no information. I came across this video which deeply confuses me https://www.youtube.com/watch?feature=player_detailpage&v=Qgy8A_GjmGo#t=112 He gets 255 Points with all characters without even pressing the "right" buttons. Ive tried to recreate this with 0 success anyone know something?