Concealed Weapons Don’t Work? [Video]

So I just watched a video recently where they did a controlled study showing that carrying a concealed weapon is not a good idea. They give a group of college students some firearm training, actually more than you get in the CCW/CPL course you take to get registered to carry a weapon. Then they give one student in the class a gun, and surprise the whole class room with a unexpected shooter and the results are scary.

After watching the video I kinda felt like they set the shooter in the classroom up for failure. It's seems like the shooter goes directly for him.  I feel that regardless of this video I would rather have a weapon to defend myself and others around me. What do you think?

Here's part 2