Thats usually a bad idea, when people look at the hip hyper extension of olympic lifters finishing the second pull, and try to mimic it by pulling "backward" or leaning back, they end up using and over arching the lower back instead of extending the glutes. If someone is way out in front with the bar then you can cue "back" to try and hit the middle, but actively thinking about it for a lot of guys can mess up the mechanics of the pull badly.
