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Derailments Caused By Emergency Braking?

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BaltACD, I understand exactly what you are saying about slack run-in being muted at higher speeds and potentially very severe at slow speeds.  That is exactly my point in questioning Mr. Hilton’s analysis in my previous post.  At higher speeds, I see the brakes getting somewhat of a hold on the entire train before the slack gets a good opportunity to run. And also, at low speed, there is not that much range to decelerate before reaching dead stop.  So that 5.5 second delay in propagation might very well allow the head end to actually stop while the hind end is still moving.  And once the cars stop, their resistance to movement jumps way up—something about bodies at rest wanting to remain at rest. But if a train is moving fast, all the slack will have run in while the head end cars are still moving, so they are not able to build up that maximum resistance that occurs with stopped cars. There might also be some effect arising from the fact that braking friction between the brake shoes and wheels is lowest at the highest speed and highest at the lowest speed.  So if the head end dynamites, the brakes will tend to really grab and pinch down the momentum.  Although, I don’t know how that exactly shakes out because they would grab the trailing cars as well just a few seconds later.
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