This discussion puzzles me. Why would you want to dig a fighting position? These things are designed for members of a military unit to take cover from shrapnel from indirect fire weapons and from machine gun fire, and typically only when trying to hold a defensive position where an assault is anticipated. If you're just by yourself or with a few friends/companions, you're much better off using your time prepping multiple hasty postions along a line of retreat or getting on the offense to disrupt and engage opposing forces. Modern engagements employ manuver warfare tactics: shoot, move, communicate. If you're gonna dig a fox hole, you might as well call it what it is: your grave.
ken