I had a same experiance with 3 guys last spring, however they never made it into my house. They got between me and my home while I was going to my mail box and returning with the daily mail.
These kinds of incidences can be very dangerious to anyone who is not really on guard for their safety. I don't walk to my mail box any more, and realize you are quiet vurnerable when leaving the safety of your home any time. I now talk to strangers through a locked door. I am not being parinoid, but just practicing safety so I can avoid being forced to resorting to my EDC because of my own actions.
All need to be very prudent where self defense is involved. I salute this guy for his reasioning in this case. He is right, what happened to him is not worth living with shooting someone, just because of their stupid actions. Any averted shooting is honorable and the final outcome was good in this guys situation. His sleep will be sweet because of his actions.