Final answer:
Commanders must assess the situation and consider alternative strategies, such as resting the unit or reevaluating tactics, to keep their unit combat-effective when a crewmember fails to progress to competency level RL 2.
Step-by-step explanation:
When a crewmember fails to progress to RL 2, commanders face a tactical decision that is critical for maintaining the integrity and effectiveness of their military unit. The passage provided suggests the severe consequences of overextending a military unit in an attempt to gain an advantage, which can result in the loss of crucial leadership if forced marches lead to exhaustion. Commanders must assess the situation and consider alternative strategies such as resting the unit, reevaluating the tactics employed, or reorganizing the command structure to ensure the unit remains combat-effective and can achieve its objectives without incurring unacceptable losses.