Sept 11th is probably what really began this process for me. It was about four years after that fateful event before I realised that what I thought I had seen, really wasn't what I had actually seen at all. The more I was presented with the details of what unfolded, the anomalies, the impossible contradictions, the more I learned that just because I had seen it, didn't mean it happened in the way I thought I had seen it happen.
Can you remind us of the original story here - before you revised it - and then give us the revised version!
Remember that the precognition might be in the form of a cartoon version, or it might be someone elses experience, which might be warped in all sorts of complex ways.
We all tend to baulk at people who tune their recollection after the fact, but shouldn't we always be wary of tuning a recollection after the fact to make it less significant?