this sounds pretty good because even if one person fails to contain their position then everybody is spread out enough that they could make it through the level as opposed to most camping techniques which when the people up front fail you get stormed from the front and all die or if zombies get through the back you get killed from behind, the only problem is you would epic fail at this if you had 3 people because for one level the front may be able to hold up with one person but for many levels they are bound to screw up.