I have used this drill myself and like he points out, it forces you to slow down to work on fundamentals like trigger control and sight alignment to make sure that you get all the hits. If you miss a shot, you flunk.
I will let Greg tell you more about the drill. Click on the source link below for Greg’s article:
“One of the shooting drills I like to use to hone my trigger control is called “Dot Torture”. It’s relatively well known among the competitive shooting community, but many recreational or defensive shooters may have never seen it.
The drill was originally developed by David Blinder at Personal Defense Training. It involves shooting 50 rounds at a series of two-inch circles (dots). The target can be dowloaded from David’s website (linked above) and printed at home for use at your next training session. I like the alternate version of the target developed by Todd Green at Pistol-Training.com. His version of the target has directions conveniently printed under each dot.”