Re: Tentative Covers & Descriptions for Upcoming Summer 2009 Trek Book
If that's the case, then there was no actual need for Kirk and Spock to go back to "repair" McCoy's damage, was there? Because their timeline should have continued to exist?
Strictly speaking, that's the way it should work. Trek has always been inconsistent about this. There's evidence that can be cited to promote both interpretations, as Roberto Orci acknowledged in his recent TrekMovie interview about the new movie's time-travel rules. But
The Chimes of Midnight does set a precedent for the continued existence of a timeline that was "corrected" back to the original onscreen. Perhaps both timelines coexist and it's simply a matter of the characters making sure they return to the right one (as Bill said).
I had assumed that the timeline in "City"/Provenance was akin to a stream that branches off from a river and then rejoins it at a later point (branching off in the 1930s and rejoining in 2267), whilst the Chimes timeline was a separate river that branches off from another one and never rejoins it.
But if that were true of the Thelin timeline from
Chimes, then why would Spock have needed to go back in time and save himself? Storywise, both timelines are treated the same way: altered realities that the characters have to go back through the Guardian to restore. So if the Thelin timeline can continue after that restoration, why couldn't the Edith-Lives timeline do the same?
Personally, my view of "overwriting" timelines in cases like "City" and
First Contact is similar to yours -- that one timeline isn't really "replaced" by another, but they coexist from the moment of divergence up to the moment of the original time travel, and then they undergo quantum collapse back into a single timeline that reflects the alterations made by the time travellers. But at the same time, we know from "Parallels," the Mirror Universe, and Myriad Universes that there are plenty of parallel timelines that don't go away -- usually because there was no time travel involved in their creation. But
Chimes -- and the new movie -- require there to be cases where an original timeline and a temporally altered timeline coexist indefinitely. Those may be exceptions to the rule, but their existence is now an established reality.
And in response to
MHJH, I don't think of the MyrU novels as "What If?" stories in the sense of "imaginary" tales of what might have been. As far as I'm concerned, they're events that "really" happened in parallel timelines. In fact, there are plot points in
Places of Exile that depend on that assumption.