...to run the Straits of Hormuz at night and get oil past the Iranians, Hence the "Dark" reference.

msn.com - Trump says US secretly moved more than million barrels of oil through the strait of hormuz

Very cool stuff:
Trump disclosed the operation earlier Wednesday during remarks to reporters in the Oval Office. The president credited the clandestine oil flows from keeping prices from surging higher.

Energy Secretary Chris Wright said Tuesday that oil exports through Hormuz are "rising very meaningfully" without elaborating further.

Dozens of ships stranded in the Persian Gulf have exited through Hormuz in recent weeks amid quiet coordination with the U.S. Navy, Lloyd's List Intelligence reported last week.

Evidently we set it up such that tankers transit to a certain point in the Gulf Of Oman, where they rendezvous with other tankers and then perform a ship-to-ship transfer of the oil. Then the original tanker slips back into the Gulf to re-load oil and no one is the wiser. The tankers are turning off their transponders and are being escorted by US drones.

The ships running the blockade were covered by the $40 billion that Treasury set aside for insurance purposes.

This certainly explains some of the downward pressure on crude prices in the last couple of weeks. Unfortunately now that the Iranians and their Russian/Chinese suppliers of intel and targeting information know about this there will need to be quite the adjustment in tactics.