"Empty chamber" is a from a Utah law. In Utah, without a concealed license, anyone OCing must have the chamber clear (two actions to fire). The slide could be retracted so both actions could be performed with one hand, but the chamber must be clear. Very probably someone from Utah or confused between their law and Nevada's. By the way, that law may no longer be in effect (they recently made a number of pro-gun law changes). Check with the folks on the Utah forum to be sure.