Instead what we find is that the immobilizing fear and indecision that Dinkheller projected throughout the incident resulted in a "one-step-forward-two-steps-back" approach in dealing with Brannan.
Had the deputy been decisive in both his words and his actions, he might well have mitigated the need for any shooting.
Don't think so? Let's suppose for a moment that this was a suicide by cop, gone wrong as some have contended. If such was the case, Brannan probably would have immediately exited the vehicle and confronted Dinkheller with the rifle, loaded or not, upon his initially being stopped.
What we see instead on Dinkheller's dashcam video is a growing synergy between the two men, a literal dance of death that first finds Brannan prancing around with taunts for the deputy to shoot him. When Dinkheller's obvious disinclination to do so becomes apparent, an emboldened Brannan doubles back to load his rifle in plain view of the deputy before ultimately shooting and killing him.
I can't say that a more assertive tone and determined countenance would have averted the shooting, but it sure as hell couldn't have hurt.