I have the belief that flashing guns to stop fights is stupid and dangerous. IMO Never pull a gun unless you intent to use it. just MO.
Change that to you're in fear for your life
and I'll agree. I may pull my gun because I'm in fear for my life, but as it's pulled, the aggressor runs away. It's happened many times, just take a look at NRA's The Armed Citizen.
I then have lost the intent to use it, because I'm certainly not going to shoot him in the back. Or, you could look at that as using it just as a show of force in those successful encounters. At any rate, the police should be called.