oil is less fungible than previously thought...at least right now
Key is understanding what each market actually is and where it is produced and supplied.
Cushing and Midwest refineries are oversupplied with crude, resulting in lower prices for WTI. WTI is a landlocked crude — it doesn’t move on tankers. WTI crude goes by pipeline to the key oil storage and pricing hub at Cushing, Okla., and then to Midwest refineries.