New York Times: Diluted bitumen the blend of thick Canadian crude that would be shipped by the proposed Keystone XL pipeline is no riskier to transport than other types of crude oil, a new study has found, a conclusion that came under sharp attack by environmentalists. The study, which was conducted by the National Academy of Sciences and released on Tuesday, found that batches of diluted bitumen were no more likely to corrode or damage pipelines. And it determined that pipeline operators had no reason to change...