Health site puts agency and leader in hot seat

Ten days before HealthCare.gov opened for business, Marilyn Tavenner, the obscure federal bureaucrat whose agency oversaw the creation of the troubled online insurance marketplace, had a bad omen. It was a Sunday, and her mobile device was on the fritz, forcing her to go into the office. "It reminded me that I can still be brought to my knees by a malfunctioning BlackBerry," she joked in late September, recounting her technology woes to a group of insurance executives. Nobody at the Centers for Medicare and Medicaid Services, the agency Ms. Tavenner runs, is joking now.