I don't buy that the order books are shallower than previously. I'd love to see evidence of it. People also complain that 'as soon as the markets move, the HFT

I don't buy that the order books are shallower than previously. I'd love to see evidence of it. People also complain that 'as soon as the markets move, the HFT firms get out of the way and the liquidity disappears.' As if the humans in the pits were making markets during big moves and getting run over (losing money) during high volatility. Give me a break.