text: Chapter 5
  Figure 5-10. Security force continuing to cross LD separately to
  establish a flank screen
  Security Force Crosses LD Separately from the Main Body and Deploys to Perform Mission
  5-91. In this technique, the security force crosses the LD separately from the main body, and its lead elements
  conduct a movement to contact, as seen in figure 5-11. Follow-on elements occupy positions as they reach
  them. This technique is appropriate when the main body is moving slower than in the first method (separately
  from the main body and deploys to perform the mission), the LD is uncontested, and the IPB process estimates
  possible enemy contact. This technique is slower than the previous technique (separately from the main body
  and deploys to perform the mission) but provides better security.