The Ultimate Precognition

There is a mythos about what might lay at the extreme end of the Precognitant's skill. Despite the extremes of Human efforts to master all that the diciplines had to offer - and despite the ability to read the future being one of the greatest pursuits of all of human history - no precognitant was ever quite able to read the future of a nation. Not for further than a week, and even then it only mattered if they were involved. There was little beyond their own perview.
There were statements given by those who watched the best of the precogs driven to the edge as the human empire went with them. The precogs that did not immediately rip themselves apart under their own raw strength, or immediately after by their associated skills, were oft found babbling - statements of what was to come. Predicting famines, droughts, solar events....
...at least, that is what reports say. Most data from The Scream is arbitrary; written by folks clinging to the barest of statements to feel faith in a universe that damned them to darkness. It's hard to tell if the raw power rendered by The Scream really did push them to The Ultimate Precognition - or if people just wished to hold their beliefs in the heart of a screaming god.

Summary

The long and short of the story is as such;
Powerful Precogs exist. But more powerful Precogs existed prior to The Scream.
When The Scream struck - a wave of psionic energy passing through all of drillspace - it destroyed the minds of millions upon millions of psychics. Some precognitants survived by sheer luck (Or, as they would've called it - A cosmic decision that it was Not Their Time.) but in surviving, were still driven crazy.
With their brains so heavily burnt, but their bodies staying alive, and their abilities active to save them - the power may have been chanelled into their precognition; thus giving them access to psionic powers far beyond anything that could be acquired by humankind (without the assistance of a cosmic event that destroyed the Empire of Mankind, ofcourse).
Therefore, if truthful records of what was learned were to be found (or, by some miracle, a living Precognitant was found from that time period that had not burnt themself to a crisp in unsound madness) then the Future of All may be at the fingertips of any who required it.
The final part - the rarer part - is that it is believed that such abilities could be accessed again. Provided that enough Precognitants decided (or were otherwise forced) to have their brains incinerated for the purpose.

Spread

The Myth is generally known amongst those who both hate and love Psychics. Anyone with an interest in learning on the topic will inevitably come across tales of what psychic diciplines were like before the collapse - but this one, a gem for anyone - comes up frequently.

Date of First Recording

Shortly after The Scream, Multiple Instances.

Date of Setting

The Scream