for clarinet and piano
The title contains multiple meanings: "traces" of musical materials that were not used in a recent piano piece called Toccata that I composed in homage to William Albright; and a word that refers to a person involved in "freerunning" or Parkour, derived from Parisian slang "tracer" — "to move quickly". The "obstacle" course can be found at various levels, from a substructure of two hexachords "in rotation" to the piano and clarinet "in motion."