So just how do you design with simulation? Essentially the same way you design anything. I really doubt that anyone sketches out their latest offering, just once, details it, gets it made in significant numbers, then sits back whilst the cash rolls in and the plaudits of an incredulous world provide the stimulus for the next project. I’m currently reading “Surely You’re Joking Mr Feynman” and in that amazing book he says that solving problems is about persistence. Problem solving, and what's design if it isn’t 3D problem solving, is about persistence, and through that persistence building up an understanding. Design through understanding – nice idea.