The New York Times has a long piece up on the lack of attention paid by the MMS toward the “last resort” blowout preventer. An excerpt:

An examination by The New York Times highlights the chasm between the oil industry’s assertions about the reliability of its blowout preventers and a more complex reality. It reveals that the federal agency charged with regulating offshore drilling, the Minerals Management Service, repeatedly declined to act on advice from its own experts on how it could minimize the risk of a blind shear ram failure.
It also shows that the Obama administration failed to grapple with either the well-known weaknesses of blowout preventers or the sufficiency of the nation’s drilling regulations even as it made plans this spring to expand offshore oil exploration.
“What happened to all the stakeholders — Congress, environmental groups, industry, the government – all stakeholders involved were lulled into a sense of what has turned out to be false security,” David J. Hayes, the deputy interior secretary, said in an interview.
Even in one significant instance where the Minerals Management Service did act, it appears to have neglected to enforce a rule that required oil companies to submit proof that their blind shear rams would in fact work.
As it turns out, records and interviews show, blind shear rams can be surprisingly vulnerable. There are many ways for them to fail, some unavoidable, some exacerbated by the stunning water depths at which oil companies have begun to explore.
But they also can be rendered powerless by the failure of a single part, a point underscored in a confidential report that scrutinized the reliability of the Deepwater Horizon’s blowout preventer. The report, from 2000, concluded that the greatest vulnerability by far on the entire blowout preventer was one of the small shuttle valves leading to the blind shear ram. If this valve jammed or leaked, the report warned, the ram’s blades would not budge.