Matt actually thinks that allowing the short selling of hot web 2.0/app companies could actually make prices go lower, but in actually it tends to be the opposite as short sellers have to scramble to buy back the shares in panic as prices keep going up. Oh, you think snapchat is a bubble at $4 billion..now it's worth $40 billion. Enjoy your 900% loss. Remember the Porsche/Volkswagen short squeeze fiasco?