Chuck Taylor, Masaad Ayoob and Ed Sanow have all written of this.

I'm surprised that you've followed cases so dilligently and not run across their names as expert witnesses. (I'm not being sarcastic, I'm really surprised.)

A quick call to a Virginia BCI official (personal acquaintance) also suggested that in a shooting case where a revolver is the weapon, the shooter will be asked as a matter of course whether or not he cocked the gun, and the questioning could proceed based on that answer if it is in the affirmative.

There has to be some common sense involved. It's possible that it would be entirely obvious to the investigator that there had been an intrusion and that the shooter was in fear for his life.

However, there could also be circumstances that would lead the investigator to wonder whether the gun had been deliberately cocked and aimed in an abuscade or whether the gun had been cocked as a threat and then inadvertently discharged.

By any chance, do you have access to Westlaw?