Much of HFT does have little social value. We could eliminate much of the worst of it by allowing subpenny trading, so trading firms could compete on price inst

Much of HFT does have little social value. We could eliminate much of the worst of it by allowing subpenny trading, so trading firms could compete on price instead of on latency. Maybe you think "sub-pennies? that's just a different kind of insanity." But remember that we're talking per share pricing. So imagine every transaction of every share ever being wrong by an average of half a penny. Imagine you could compete for the money represented by that error, and you could win it, just by having the fastest computers which put in the orders first. Behold: Wall Street as you know it.