If the eye shot dropped him as Gary suggests , it's pretty well known that folks have a hard time inhibiting the next shot at a stop signal. Research has shown this and if there is a trial, the defense time needs to call the appropriate folk.
Yes, with the caveat that none of us know much about the actual facts yet, most non law enforcement don't know the training on firing until the threat stops. The empire state shooting by two FBI trained NYPD officers illustrates this training. Brown was unarmed, but if he had already grabbed at the officer, and was heading back at him, a grave threat was arguably present.
Overall this case illustrates a gulf between policing and civilians, and secondarily and worse a sensationalist bent in the press. If experienced police/crime beat press had been the main gatekeepers, the false memes that the Ferguson police were withholding info, or released the robbery footage to "smear" Brown, would have never been an issue.
Brown's assault in the commission of a robbery, even if Wilson did not know it, goes to Brown's state of mind. It is highly germane to the shooting, It makes him much more likely to flight or fight, because a) he was hyped up ; b) because of the likely penalty (felony arrest for the crime minutes before) of complying; and c) because it shows him capable of criminal violence. The main witness, Darien Johnson, is also a suspect in that assault and robbery, and has prior cases of lying to police, including false report filings.
And there is little to no reporting of the fact that the assault and robbery info was released because of media FOI requests combined with Missouri's sunshine laws which mandated release of the info. The press calling that a smear when it was press FOI requests that triggered it is ironic.
While the case also touched on both militarization of police and race issues, there is no evidence so far that those issues have anything to do the actual primary incident