I am sorry I cannot do your podcasts, I am on dialup, but I will give you a suggestion on where to look about some thing that could be considered as to when to shoot and when to not shoot.
Several years ago (2005) there was a man that entered the Tacoma Mall and randomly stated to shoot the place up. There was another man there with a CPL who drew his pistol and commanded the shooter to cease.
The shooter then turned on the CPL holder and shot him several times (5). The CPL holder almost bled to death.
Obviously, if the guy is already shooting, you don't bother with the warning, you just drop him.
A semi-complete version is in this wiki article:
http://en.wikipedia.org/wiki/Tacoma_Mall_shooting