Today's hypothesis states that all free jazz improvisation demands the musicians maintain the music's vigor like a juggler, to all appearances, keeping all the balls in the air at once. Proof of this theory is the opening piece "Train Track" from alto saxophonist Mette Rasmussen and drummer Chris Corsano's release All The Ghosts At Once. The music opens with wavy Evan Parker-like saxophone notes and cymbal scrapes that evolve into unblended energy jazz. The duo produces a buoyant sound, part primal energy drive, part liberation.By