I ran across this quote in Peopleware:
The chemistry-building manager take pains to divid the work into pieces and makes sure that each piece has some substantive demonstration of its own completion. Such a manager may contrive to deliver a product in twenty versions, even though two are sufficient for upper management and the user. It may even be necessary to conceal some of these interim versions form the client and build them only for internal confirmation and satisfaction. Each new version is an opportunity for closure. Team members get warmed up as the moment approaches, they sprint near the very end. They get a high from success. It suffuses them with renewed energy for the next step. It makes them feel closer together.
— Peopleware 2nd Edition pg. 152
Way back in 1987 Demarco and Lister described a pretty good version of Scrum and why it works. Other than the idea of the non-transparent idea of concealing some of the demos of the versions it aligns almost exactly.