Sometimes a solution is obvious to me and I just jump in, do it, and then document with photography. Less obvious problem/solutions are solved by modeling which then become renders. Even though I render, I really think of my sketchUp/render work as prototyping and testing. The computer has streamlined work flow. For me sketching, working drawings, documentation and presentation art are no longer separate projects. The line between these process becomes more and more blurred as technology begins to bridge the gaps and integrate the disparate elements into one continuum.
I would like to model the fiber optic lights although I have not figured how to go about it yet. I use twilight render and don't know what chices I have for propagating or bundling the fibers efficiently.