What tactic involves a designated element pitching back while the other continues until pitchback criteria is met?

The tactic in question is known as DELOUSE. This maneuver is commonly used in aerial engagements where one element of an aircraft formation is tasked with pitching back—essentially pulling away from the primary engagement—to create a defensive posture or to regroup. The remaining element continues its mission until specific criteria for the pitchback are satisfied, which typically involves the tactical situation on the battlefield or engagement conditions.

In this scenario, DELOUSE allows for maintaining an offensive approach while ensuring that at least one of the elements can manage threats or reestablish positioning. The coordination inherent in this tactic is crucial for ensuring the effectiveness and safety of the formation as they operate in complex environments.

The other choices represent different tactical maneuvers not related to this specific action of allowing one element to back away while the other maintains engagement. STAGGER refers to a formation that spreads out units to maximize coverage or minimize risk, ENGAGE typically describes the act of initiating combat, and HOLD is associated with maintaining a position or state rather than maneuvering elements in the described manner.