Comments by "ncwordman" (@ncwordman) on "Train To The Future | Back To The Future 3" video.

Doc hadn't met Clara when he saw the photo of his gravestone.
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@struttux5156 In the original history she died in the ravine. When Marty went back in time, as we see in the movie, they saved her.
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@struttux5156 Oh weird. You're right. Hmm. Oh wait! I forgot: There are three versions of Clara and the ravine. In the original, she dies; second is when the Delorean is struck by lightning in part 2, and Doc goes back in time: He picks her up at the train station, thus preventing her death--which he was unaware of; the third is when Doc rescues Marty from Tannen's gang in part 3, finds out he and Clara were in a relationship, and chooses to not pick her up at the train.
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