John D. Rockefeller’s empire wasn’t founded on owning oil fields but instead the means to process and transport oil. Alongside cementing his ruthless reputation, the efficiencies generated by Standard Oil led to a collapse in kerosene prices in the late 19th century. One rationale for Energy Transfer’s interest in Williams: its pipelines in the northeastern U.S. Gas flows have shifted dramatically as shale’s development has opened up new supply sources, not least the giant Marcellus Shale in the Northeast. Last year, this accounted for a fifth of U.S. gas production, according to Sanford C. Bernstein, largely meeting regional demand. But this is set to increase to one-third of U.S. supply by 2018, Bernstein estimates, helped by new and modified pipeline capacity allowing more gas to flow from the Northeast. Right now, bottlenecks there mean Marcellus gas often sells locally at big discounts to the already-low Henry Hub national benchmark. […]