Board Thread:The Panopticon/@comment-24361711-20151205212506/@comment-1293767-20151205235652

The "run you clever boy and remember" was a mnemonic device Clara Prime came up with to remember the Maitlands' Internet password. That was the last thing she said before jumping into the Doctor's timeline and it was passed onto (at least) the Oswin Oswald and Clara Oswin Oswald echoes.

While Clara was still in the Doctor's timeline, she told the Eleventh Doctor that he was the eleventh, indicating her echoes never encountered War or Twelve, or at least she didn't remember if they did. As far as I recall, that's the only on screen indication she had any sort of memory of her echoes' lives.

According to Into the Nowhere, a short story by Jenny Colgan which this wiki considers as valid and thus equal to television continuity, Clara could only remember fragments of her echoes' lives and some recollections were so limited she only recalled them as dreams.

Unless there are any other stories I haven't read personally, that's the only story I know of to directly reference the issue. Blood and Ice does deal directly with Clara meeting one of her echoes, but I haven't read it myself. From what I know of the story, it sounds like Clara is surprised to meet the echo and doesn't inherently know if Winnie's life, which would indicate to me she doesn't remember it, but I don't know if the story makes any reference to her remembering part or all of any of the other echoes' lives.