Good article. The author is 100% correct that you should never draw or present a firearm unless you are willing to use it. I would add that command presence should be asserted before the firearm is drawn. For most police agencies, "Command Presence" is considered the first level of force in use-of-force assessment. It is generally accepted in law enforcement that taking control of a situation in an assertive manner can prevent the need for any additional force.
I understand that suspects obviously know that officers are armed, even if they haven't drawn their weapon, but command presence is considered a crucial skill in police work that can carry over to civilian encounters. Being confident, alert, and assertive can prevent many situations from escalating. Criminals are lazy by nature, and are always looking for easy targets. Giving people the impression that you are willing and able to fight them is one of the best ways to avoid having to actually do it.