I lived in the back alley of San Francisco, so I have been mugged, stolen from, and jumped. I don't have the same experiences here in southern California, though my roommate was mugged just a block away from where we live. So long as you don't die, these things give you street smarts. I have never had any of these things happen to me twice, mostly because by being aware you can intimidate people, or even confront them. I don't know for sure, but maybe the reason they didn't mug you James was because you could see that they were being suspicious.
I have had a few instances where I have avoided potential threats around this area. Back when I was in highschool, I didn't drive and my guardians sure weren't gonna pick me up, so I walked to and from school. Eventually I made freinds that also walked home, but before that I was walking a mile and a half everyday alone. One incident I remember was a group of four Mexican guys walking ahead of me kept turning there head around to look at me, and then talking to eachother in Spanish. I picked up on gringo so I figured they were talking about me. I just simply walked really really ridiculously slow. They slowed down a little at first, but then just started walking normally again.
On a much scarier incident, me and my two Asian anime/video game club friends and I were petitioned for money by a group of around nine guys, most wearing the same black sweatshirts. (a gang color of the Center Street Locos) They asked for a dollar, but I know that is a tactic for seeing if people have any real money on them. On that occasion I just lied and said I didn't have any money, neither did any of my friends. I put on quite the performance, even when they threatened to check me... but I guess I am a convincing liar. In that situation I knew that if I did pull out my wallet it would have been gone though... so I really didn't have much of a choice.