CBC?s Barbara Frum sends thanks for explanatory backgrounder

When attempts were made to explain the extent of the damages, their eyes would glaze over after point number two. You could see them glaze over, even over those old telephones. Meanwhile, people were being caused preventable harm in several known high risk groups. Bearing witness was like watching a train wreck, with dozens of trains ending up in the carnage because engineers received yet ignored repeated, clear and legally-obligating signals.