This is an old technique that was recently reborn as part of ResponsibilityDrivenDesign and CrcCards.
Situation:
A group needs to understand or evaluate a fairly complex proposal.
Forces: Many parts interacting vs many people can act in parallel.
Solution:
Each member plays the role of one part of the proposal and the group play acts the whole thing. People can also act as Recorder and Observer. In software the people are objects and the recording is done on cheap disposable cards or sticky notes.
Related Patterns: MakeItVisible, ObserverReviews