I read an article in the news about how the Norwegian kroner rate has suddenly started tracking the Swedish kronor rate instead of the oil price, after some changes in the market affected both currencies simultaneously and the trade bots latched onto it, creating a self-fulfilling prophecy.
If the stock market was an MMO game, the bots would've been banned a long time ago. We can't have bots in control of the market. An auto-pilot should take you to your destination, not choose it for you.