The Curse of Knowledge
Tappers expected half their listeners to name the song. Three in 120 did. Once you know the answer, you cannot hear your own message the way someone without it hears it, and that includes your team's top priority.
The curse of knowledge has a clean demonstration. In 1990 Elizabeth Newton, a Stanford psychology PhD student, sat pairs of undergraduates back to back. One finger-tapped the rhythm of a well-known song. The other tried to name it.
Tappers guessed their listener had about a 50% chance. Listeners got 3 songs out of 120, or 2.5%.
The tapper hears the melody in their head. The listener hears knocking. Newton then told a separate group which song was coming and tapped it for them. They also predicted that half of listeners would get it. Knowing the answer made the tapping sound obvious.
A year earlier, Colin Camerer, George Loewenstein and Martin Weber (1989) had named the effect: better-informed people cannot set aside what they know, even when ignoring it would pay. Trading in a market cut the bias by about half, not to zero.
A leader has heard the full melody of the priority in every strategy meeting. The team gets the taps: a slide, a message, a line in the all-hands.
The nudge: Ask one person to tell you the team's top priority in their own words, without prompting. If you hear a different song, fix the tapping.
Source: Camerer, Loewenstein & Weber, The Curse of Knowledge in Economic Settings: An Experimental Analysis, Journal of Political Economy (1989); Newton, The Rocky Road from Actions to Intentions, PhD dissertation, Stanford University (1990)
