Was the timeline shown in "The Visitor" erased? The quick answer would be "of course it did". However, I'm not so sure. Some of the comments the adult Jake made suggests at least the possibility that somehow while Captain Sisko returned just before the accident that created "The Visitor" timeline and thus the timeline should have been erased that it actually went on. What makes me wonder is the comments about publishing posthumously and the advice he gave to Melanie just before she left. Sure, he may have said these things in case his plan failed. I mean, he had no margin for error as far as timing went. If he had taken the drug and died before his dad arrived, nothing would change (timeline-wise) and by the same token, had he died just after his dad disappeared, nothing would change. So that's possible. However, the adult Sisko besides being a writer was a scientist and was shown to have had a good grasp of physics. Therefore, perhaps he realized that by setting his dad free a new parallel timeline would be created where the 18-year old Jake wouldn't lose his father and he himself would no longer have the pain and regret because he would be dead. What do you all think?