(statistics show that if you present a firearm and show weakness in using it, even in a life-threatening situation, it is more likely to be used against you)
First, the urban legend: New grads of the FBI academy are told the armorer will be at the graduation ceremony to file off the front sights of their handguns. A few new grads look at each other; finally someone asks why? Because if you're not going to use your gun, someone will take it away and shove it up your ass. And it's a lot better with the front sight filed off.
Second, the other side of that coin is presenting a firearm when there's no life-threatening situation. I've seen more COPS episodes where the cop draws a gun on some guy standing in the street, only to have the guy turn around and walk slowly away while the cop yells HALT! and holds the gun on the guy's back. He can't shoot, and he's pulled his gun. What's he going to do now?
My lesson is that drawing a gun is a mistake if you aren't being threatened and have a reason to use it upon drawing it. Am I wrong?