When OPEC points at U.S. oil producers, it always blames the shale drillers for oversupplying the world market.
But while shale is in resurgence, the real source of recent growth has been the offshore drillers in the Gulf of Mexico.
According to Bank of America Merrill Lynch, U.S. oil production growth between September and December was almost entirely the result of offshore wells, which increased production by 220,000 barrels a day in that period.
Offshore projects are much more long-term investments. They are far more costly to develop and take years to get started. "Those projects have an inertia," said John Kilduff of Again Capital.