CONCEPT
Practical Drift
Scott Snook's extension of Vaughan's framework — the gradual divergence between how work is supposed to be done and how work is actually done under the pressures of daily practice, producing a gap between doctrine and reality that no single decision creates and no single correction reverses.
Practical drift names the structural phenomenon in which formal standards and practical standards diverge through the accumulated weight of competent adaptations. Snook formalized the concept in his 2000 study of the 1994 Black Hawk friendly-fire incident, demonstrating that the gap between doctrine and practice is not produced by disobedience but by the ordinary operation of institutional life — by practitioners solving the problems in front of them, reconciling formal requirements with operational realities through countless small accommodations. In AI-augmented knowledge work, practical drift operates with particular severity because many formal standards are implicit rather than codified, making the drift doubly invisible.
In The You On AI Field Guide
Snook's contribution, built directly on Vaughan's framework, was to demonstrate that practical drift is structural rather than behavioral — that it emerges from the mismatch between static formal standards and dynamic operational environments. The formal standard is designed for