The 2-minute rule + one inbox

Across controlled experiments, unfulfilled goals produced intrusive thoughts and degraded performance on unrelated tasks (a working-memory cost). Prompting participants to make a SPECIFIC plan for the unfinished task eliminated the intrusions and restored performance to baseline WITHOUT completing the task. This is the direct mechanistic basis for 'capture it into one inbox so the open loop stops eating working memory.'

Series of controlled experiments (N~172 each) showing that externalizing information (cognitive offloading) reliably frees working-memory resources and boosts immediate task performance, especially at higher memory loads. Supports the 'one inbox' externalization step, though it documents a tradeoff (offloaded items are less well remembered internally) which is irrelevant here since the inbox is meant to be re-read.

RCT in 81 adults with ADHD: a structured, goal/plan-implementation intervention (Goal Management Training + psychoeducation) improved everyday executive functioning, wellbeing and reduced ADHD and anxiety symptoms. Indirect support: structured externalize-and-plan systems help adult ADHD executive function — but this tests GMT, not the GTD 2-minute rule / single inbox specifically.