Connector schemes almost always provide a mechanism for keying that will not allow the connector to be mated with it's counterpart in any way other than the correct way. This is especially important when dealing with hazardous voltage levels - AC line voltage would be one of those. So how do you suppose the stage pin connector scheme ever got UL approval when it is able to be partially mated at 90 degree angles? This would allow connecting a pin in the plug to any receptacle pin that I would choose and essentially have the capability to apply line voltage to any pin on the mating connector. That means I could, if I wanted, connect line voltage to safety ground of the connected device - not to safe. It's obvious that no one would intentionally mate the connectors in this manner, the point is that there is no mechanism to prevent it. Any thoughts.