No one really cares if it's under control in a PL contest, just keep your hands on the bar as you lower it. This applies to the gym as well. Lowering it under control is bad for your back and bad for your workout.
If they give you dirty looks, fuck em. Until management TELLS you to stop dropping weights, it doesn't matter. And if they do you might want to look into a gym that respects the rights of lifters instead of the complaints of the people who went there for a nice relaxing workout while listening to soft rock.