Humans never learn and apparently neither do robots. Autonomous trading AIs went on a spending spree at Knight Capital Group in New Jersey this week, buying up shares in everything from RadioShack to Ford and American Airlines (ouch) in a 45-minute frenzy of disobedience. The company tried to offload the unwanted stock, but discovered it was already nearly half a billion dollars in the red -- enough to wipe out its entire profit from 2011 and "severely impact" its ability to conduct business. If only it had protected itself with one of