I now know why it is called "guard." Some pilots guard it with their life, never to be used, even if used as intended. TOTD....the FO I was flying with, when someone advertised their "short final to 22" on 121.5, and someone came back with "you're on guard," says to me...."Those Air National Guard buddies, always get upset when someone accidentally transmits on their frequency!" She seriously thought "guard" meant Air nat'l guard!