There is a lot of triumphalism about fracking and reserve growth, but it needs to be remembered that these reservoirs are much smaller than conventional plays, meaning they deplete much faster. It means a constant treadmill, and assumes future plays will be as economic as past ones. That is not a terribly safe bet, especially given the history of fracking exploration in locales such as Poland. Even California would not necessarily yield good commercial results, even if all the current and proposed restrictions were lifted or not enacted into law. A Sanford C. Bernstein study concluded that fracking would at best keep California’s oil production declines at bay, but would be unlikely to result in a Bakken-style oil boom.