Six weeks ago i posted about a new draft of the solar thermal power plant designed for Cernan's Promise. Oh how it has changed since then. The process of improving that model has been an important test case of how to elicit input on a design, and work through improving it, with online collaborators. Once again, it was done mostly by consultation in our chat room on space.stackexchange. The conversation there goes on for pages and pages, supplemented by sketches and links.