open range trading is a form of risk management, the closer your buys are to it and sell stops below it, as the price heads above the open range, it tends to test previous session highs. And same for price below open range, it tests previous session lows.
open range trading takes your own opinion out of the market, and you just trade it robotically.
the drawback is a quiet day when price just meanders in and out of the open range, and your stops on both sides keep getting hit, and pit traders will do it to you so they bank the difference.