Problem Moses Carver (Spoiler)

[hpr7]

Hi guys
I'm rereading the Dark Tower’s saga for the second time.
And I'm wondering:
If Eddie,Jack ad Susannah came from a world which is not Keystone's one how it is possible that the Moses Carver (keystone world) remembers susannah's disappearance?

[pathoftheturtle]

Good question.

http://www.thedarktower.org/palaver/showthread.php?14675-What-would-have-happened-if...&p=681623&viewfull=1#post681623

What happened to Odetta of Keystone Earth (this is boggling my head)- spoilers... (http://www.thedarktower.org/palaver/showthread.php?16163-What-happened-to-Odetta-of-Keystone-Earth-(this-is-boggling-my-head)-spoilers...)

Probably the better way to phrase it is: Is the world that Stephen King lives in really different from the one(s) that Eddie, Jake and Susannah came from, and if so, how is it possible that Moses Carver lives there at all?
Of course, there theoretically could be an alternate Moses Carver not related to Susannah, but that's a theory leading to a whole different line of questioning. Maybe, maybe, there are alternate Stephen Kings, as well. What proof do we truly have that "Keystone Earth" is actually so key in an absolute sense, other than the intuitions of a few characters here and there during their TDT adventure? And considering how the two versions of Charlie the Choo-Choo merged into one, it's even possible that the world that the ka-tet came from does not always remain an independent world, even though their memories never completely changed.
But you have to start somewhere.