Final answer:
It is true that the Assistant Controller should reiterate safety instructions for clarity and redundancy. This practice ensures that all participants understand the necessary precautions, even if they have been briefed before.
Step-by-step explanation:
The question relates to the procedures and communication protocols necessary for ensuring safety in an environment where an Assistant Controller is involved. To address the student's question: it is true that the Assistant Controller should emphasize the instruction "everyone grab hold of the loop with both hands" even if the briefing has already been conducted by other staff members.
This redundancy is crucial for safety and ensures that all individuals, including those who may not have paid close attention to the original briefing, understand the important safety instructions. Furthermore, in high-stress situations, clear and repeated instructions can reinforce the importance of the message and ensure compliance.