The Norman is a special case. It is in better condition, and looks cleaner, than bikes I've bought new and commuted on for only a couple years. The chrome is spotless, and the aluminum looks clean. The frame and fenders have a faint patina, in that the color varies a little depending on exposure to the sun etc, but other than that it's in almost showroom condition. And it hasn't been restored. That you would want to keep it in that condition, as much as possible, seems a no-brainer to me.

With a restored bike (especially a repaint) the decision is trickier. If the frame is repainted, and all the components are like new, then you've re-created a showroom like condition, then I would probably would want to keep that. But if the frame is repainted, and the components all have a weathered and worn look, then I'm not at all sure I'd want to try to make everything clean and polish anything. It would just exaggerate the disparity in condition.