Because the "double staccato" (repeated staccato notes obtained with a "tk" like pronunciation) is one of the most effective articulation techniques on the Paetzold flute, it has become an idiomatic gesture in the literature. It can be notated in different ways: either showing graphically the idea of fast repetition, as rhythmical texture or in a more simplified way with the indication of articulation (tk) in a situation where position changes continuously so that long lines are useless:
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Double staccato, which is very effective at any dynamic level, is particularly idiomatic in situations where overblow is used, as it enables the player to select and switch harmonics overtones precisely and with much agility.