I don't know where to call this from an investiture standpoint, but I think in terms of the flow of the story it would be hard to make work. If ia shardblade no longer kills the soul of the limb, does it have no effect at all on surgebinders, if so it is somewhat worthless. But if it instead just cuts their flesh like a normal blade it would basically have the exact same effect since it would cut through weapons and armor with no resistance, making them more deadly because not only do you not have a limb but you have to worry about blood loss. Like the theory it just doesn't seem practical to the story.
Because you are a guy with a cool sword and your wealthy, bored, stupid, curious, and feeling a little destructive. All adjectives that I might use to describe the Alethi upper class.