A commander who must remain awake for the plan to work has left the organization dependent on a single point of failure. In the current Crucible, candidates submit a watchbill before the scenario begins to change. Relief is part of the assessment.
During the communications exercise, directing staff may remove a simulated channel. They do not remove the real safety channel. Students must understand the difference between an obstacle in the scenario and a condition that requires the exercise to stop.
Examiners look for a readable handover: what has been confirmed, what remains uncertain and which decision cannot wait for the next conference. Endurance may help a crew through a difficult hour. It cannot replace a second crew.