I will say that you should never pull your weapon on somebody unless you intend to use it. If you pull it and don't use it your situation could go from bad to worse.
No, you pull your weapon if you feel you or someone you wish to protect is threatened with grievous bodily harm. You don't
have to use it, though. Command voice interactions can cause the BG to desist.
Since the vast majority of defensive gun usages are deterrent - the proposition in the quote is not supported empirically.