Excellent question mserr . . I guess I never thought about OC in any way other than strapping on the old OC belt holster and letting it all hang out. To me I would think OC is when someone could say "LOOK, HE/SHE HAS A GUN !!!!" and of course that is certainly NOT the effect you would be seeking. I, like AH.74, recall reading something like he has stated, that it is OC when visible from 3 directions or discernable/identifiable from 3 directions. Some time ago I was talking to a New Mexico LEO friend, and we were discussing OC, he used the term "observable" and did not specify multiple directions. There HAS to be some sort of language in some legal doc that does discuss this, maybe someone who knows where to find this will speak up.
CD