I suspected as much. A general solution would spend more time inspecting than processing I suppose. Grooves on a single (non-extruded) face should be quite simple, but I imagine the code would vary from solving the edges that turn corners. Edges that support co-planar faces and turn corners is a different procedure than those that turn corners and support non-planar. Also edges that form a "C" as opposed to closed loop would be processed different as well. Could there possibly be a prompt to help the script identify the situation before the process runs? It appears there is an overwhelming desire and need for the (universal) script, across many different industries, but I certainly understand the nature of edges in sketchup and the inability to identify them as they have no "normals" like faces do. I'm however, still hopeful for a solution.