It's sort of an extrapolation of the old concept: People are really polite at gun shows.
I think Rabbit that you have just made the best CCW/pro-2A argument ever. When was the last time you heard of a mass shooting, armed robbery or car jacking at a gunshow? Yet there were all these guns around. Aren't they supposed to cause violence?

Letting people know you are armed won't get you out of all trouble, and in some cases might invite it, but given that most crimes are impulsive, I would bet 9 out of 9 1/2 muggers will go for he unarmed guy rather than the one who is open carrying.
FQ13 Who thinks a comment of the day award is in order