Saudi Arabia’s subtle change of energy policymaker line-up since the accession of new King Salman in late January appears to give the monarch’s inner circle a firmer hand on the kingdom’s oil strategy than previous rulers have enjoyed. The most notable change was the promotion of the king’s son Prince Abdulaziz bin Salman, long a member of the No. 1 crude exporter’s OPEC delegation, to the role of deputy oil minister from assistant oil minister, a post he had held for many years.