i love that logic. lets all gather tightly for the shooter to better kill us.
My school does this as well.
One of my teachers had us do a drill, and we were told to all huddle like this:
|-------------| X = door
X | | = wall
| | - = wall
| | O = window
| S O S = us
|-------------|
I asked my teacher why we were being told to huddle in clear sight of a window, she just blew off my question. I mean seriously what