The piece has either the viola backing track throughout or a live viola player. Both provide a constant Bb (on detuned C string). The viola and oboe must work out how the sections are approached and the viola part can be improvised and include change in register and timbre.
There are no dynamics or phrase markings in the oboe part. This is to encourage the oboeist to decide these themself in relation to the detailed descriptive markings; both of technique and emotional quality.
Movement is encouraged in the performance. Either by oboeist, or viola player, or both.