text: Defense
  Delay from Alternate Positions
  7-179. Delay from alternate positions can be used when a force has a narrow area of operations or has been
  reinforced to allowpositioning in-depth (see figure 7-19). This is the preferred method of delay. One or more
  maneuver units employ this method to occupy the initial delay position and engage the enemy. Other
  maneuver units occupy a prepared second delay position. These elements alternate movement in the delay.
  While one element is fighting, the other occupies the next position in-depth and prepares to assume
  responsibility for the fight.
  7-180. Units occupying the initial delay position can delay between it and the second position. When the
  delaying units arrive at the second delay position, they move through or around the units that occupy the
  second delay position. The units on the second delay position assume responsibility for delaying the enemy;
  the delaying procedure is then repeated. Moving around theunit on the next delay is preferred because this
  simplifies passage of lines. The alternate method provides greater security to the delay force and more time
  to prepare and improve delay positions. Normally, when delaying from alternate positions, the BCT
  commander does not maintain a reserve. The forces not in contact with the enemy are available to function
  in the role of a reserve if needed.
  Figure 7-19. Delay from alternate positions