We all make up our memories. We take one part of what our senses actually tell us and two parts of what we thought we already knew, add a cup of plausibility and a dash of continuity and viola! An absolute certainty.
Whether 50 minutes or 50 years it is the same except that after 50 years we've had many more opportunities to reinvent each episode.
Still I find it disconcerting when a party to the event informs me not only that my memory is false but also provides a well organized summary of why the story as I remember it is contrary to all plausibility. ("At the time you reference I had already inherited the six gold mines from my great uncle and so I would have no reason to shift through the municipal landfill for broken bits of gold. And furthermore ...")
In actual reality there is very little which is less reliable than a memory of a 50 year old event to which you were merely a passing observer and for which you have no corroborating evidence whatsoever.
Still I find it disconcerting to be assured that is so.