On a similiar anectdote, we were told this one in my CHL class.
Husband and wife own a bar. Close it up late one night (he's carrying). Come out to find a large, african american male rifling through thier mail in thier suburban. They tell him to get out and leave. He gets out and stares him down and says "Wut...are you gonna do?" and walks slowly towards owner. He goes on to say "I know where you live, I have your address - you and your family are dead." He gets close enough and goes to punch the owner (no gun drawn...yet).
During the scuffle the BG's shirt is ripped off to reveal the tattoo "#1 Crip" or something like that. Does the threat have more credibility now?
BG leaves, owner follows guy (dumb I think...maybe). BG goes to park under bridge, finally turns and approaches owner, says "I'm sick of this $#%@" and lunges swinging at owner. Owner draws, fires striking BG two or 3 times. Cops show up, take notes, no charges filed (if I remember correctly).
Granted - the self defense shooting happened DURING an immenent attack.