Jon Udell: Extreme design versus extreme programming.
Quote: “Central to Cooper's methodology is the documentation and analysis of personas. These are carefully thought out representations of key actors (Lucy the sales rep, Bill the investor) that aim to capture the goals and motivation of these actors. From these you deduce what tasks they perform according to what priorities, then derive the requirements for interactive software behavior.
Where Cooper departs radically from some now-fashionable practices — release early and often, extreme programming — is in his insistence that designs can and must be worked out in essentially complete form on paper, on whiteboards, and in the brains of the designers, over a long period of thoughtful iterative refinement, and then delivered as a complete description of the personas, their goals and tasks, and the required software behavior. In other words, a specification.” [Serious Instructional Technology]