There is no cure all, and that is not what FRA has said. There are possible failures in every system made by man. We learn from our mistakes, we apply our best technologies, and we move on. The railroad telegraph caused many a train accident due to falty transcription from human error or shorts in the circuits, but it was better than no communications at all. It made trains safer. PTC will only make most mixed and higher speed operations about 999 times safer, not a 1000 times, so what? That's a hell of an improvement.

The newer technologies of multiple redundant systems and muliple detection, comparison, and communications modes will be better than a single point communications system like Metro had, and less prone to single point failure. In this tragic case it appears to have been a detection and/or communications failure, although I'll wait on the final assessment, because many of these accidents can be multiple failure events. So PTC will not be perfect either, and the FRA and the Railroad Safety Act were still absolutely right to mandate it. Or, maybe we could go back to the telegraph, instead of using todays advanced technologies to improve safety?

Given some peoples logic, I guess we would not have left the caves, because the first bow and arrows, weren't alway perfect against those saber tooth tigers??? But, I'm kinda glad we did.....