The research, plainly
Kahneman and Tversky named it; Buehler's studies measured it: people predict finishing far sooner than they do, even with full knowledge of their own past overruns. The inside view of the plan blinds us to the base rate of reality.
The receipt: Kahneman & Tversky, 1979; Buehler et al., 1994
What it means for events
Every run-of-show is optimistic fiction. Sessions run long, transitions eat minutes, the demo needs a restart — and the buffer you added isn't enough, because it never is. Cut content in the plan, calmly, rather than on the day, brutally.
Where to run it
Agenda math
Whatever the segment needs, schedule less content than fits. The cut you make in planning is the peak you save in delivery.
Rehearsal policy
The full technical rehearsal exists because the inside view lies. Time everything against a stopwatch, not a hope.
Project timelines
Take your event build estimate and apply your own history to it — the base rate is the truth your plan is avoiding.
Seen in the wild
Related concepts
Now use it
Score your own event against principles like this one — or make the whole vocabulary official.
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