The second person starts the process 1 person-space behind the front of the line. Every person who takes a break and moves to the back moves the front of the gr

The second person starts the process 1 person-space behind the front of the line. Every person who takes a break and moves to the back moves the front of the group back by one person-space. From an individual perspective, how is it any faster than walking alone (or everyone taking the same break at once, assuming they don't take any time to regroup or string out). If it isn't more efficient from any given person's perspective (for all of the walkers), it isn't better for the group.