The comments from Sheffield, who is retiring soon, were perhaps the most concrete sign yet that the fittest US shale oil producers will survive the price crash that started in mid-2014 when Saudi Arabia and Opec moved to pump heavily to win back market share from higher-cost producers.
Dozens of shale companies, many with marginal assets, have filed for credit protection in the biggest wave of corporate bankruptcies since the telecoms crash of the early 2000s.
