Dacres reached the Admiralty as a vice admiral rather than waiting for promotion to the Navy's highest flag rank. In ordinary service seniority, a vice admiral was junior to a full admiral and could not simply command him. Membership of the Admiralty Board changed that relationship because a Sea Lord issued orders through the delegated authority of office. The distinction between personal rank and institutional position was essential to making centralized naval administration work.
Notable Point · 2:45:23-2:47:04
Admiralty office could override an admiral's seniority
See how a vice admiral serving as a Sea Lord could issue orders to a more senior full admiral because institutional office carried its own authority.