ABC news staged an active shooting scenario with random individuals and it went as expected:

[Straw Man]

4. I've seen it many times.

It's more rigged than a North Korean election. First, they're wearing those ridiculous gloves, which have no other function than to reduce their manual dexterity. Second, the helmets restrict their vision and movement. Third, the long, baggy shirts inhibit their ability to draw the weapon. Finally, the assailant knows exactly who has the gun: it's the person front-and-center. That's who he goes for immediately after shooting the "instructor."

And despite all this, Danielle manages to land a disabling shot on the assailant, hitting him in the inner thigh. Although she would have died in the attempt, she inflicted a wound that would have severely limited his movement and possibly (think femoral artery) eventually caused him to bleed out and die.