Ask anyone who the default road guard is during a movement formation where no road guards have been designated and they are likely to say that it is the second guy in the far left and right rank.
I’ve seen it at every unit I’ve been in. We’re marching somewhere, the cadence caller shouts “Road Guards, Post!” and there is a short delay until some salty Team Leader yells at the soldiers in that second spot, telling them that they are the default road guards. Then those two soldiers will run to the intersection, getting there moments before the main body gets there and while nearly getting themselves killed in the process.
Well, this isn’t doctrine.
It’s not a regulation. It’s just a standard operation procedure that appears to have been pretty much adopted Army-wide.
Reference to the practice cannot be found in TC 3-21.5 (Drill and Ceremony) or FM 7-22 (Army Physical Readiness Training). The best I’ve been able to find are some Air Force ROTC videos that reference the practice of assigning dedicated road guard prior to the movement (you know, the ones that get to wear the reflective vest or carry the flashlight).
True, this really isn’t a myth, but I’ve watched NCOs lose their minds when that second person didn’t react instantly to the command of execution of “POST!”
Best practice would be to assign road guard prior to any movement than relying on a shaky Army-wide standard operating procedure.