This is long in exposition, but it does discuss things in an interesting way.
http://www.nytimes.com/2016/01/31/magazine/the-wreck-of-amtrak-188.html?_r=0
Hmm, that is written terribly long! And it seems premature: “In the first week of February, the N.T.S.B. will release the “docket” from the 188 investigation — a voluminous preliminary report comprising raw data from the train’s black box, imagery from the site and notes from investigators. Its ruling on the probable cause of the accident will most likely come this spring.”
A possible positive outcome: “”"“My hope,” Feinberg told me recently, “is that the derailment was our long-overdue wake-up call that we need P.T.C. — that we owe it to passengers and rail staff to have it online.”"""