I wrote a small bit of slideware on the topic for my lessons. I often refer to the “funnel” talking about process and methods but I lacked a handy reference. In terms of analytic clarity, I think the best representation is in Buxton, Sketching User Experiences, p. 144, that is based on Laseau, Graphic Thinking for Architects and Designers. Buxton discusses the topic also in relation to sketches vs. prototypes and other point of views. In my slides below you just have the combination between “divergent” and “convergent” phases. The classic scheme from J.C. Jones is still the underlying essential reference, although his specific terminology for the different phases has not achieved common usage.
One question that I can’t answer: who has been the first in talking about the “design funnel”? Who has been the first in using the “funnel” metaphor to express and represent the design process? (Yes, I checked on Wikipedia, maybe too quickly).
PS: yep the post title is a play on the Mythical Man-Month