My vote is that the publisher will absolutely split it into two books. It's almost a surefire cash cow for them.

I wonder what it would be like to write someone else's story? Would it be somewhat easier because the plot is already laid out and your own personal investment, or emotional connection with the characters somewhat tempered?

I'd imagine it would be a frightening and daunting task to finish up such a huge piece of literary work.

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"Nothin' up my sleeve. . ." --Bullwinkle J. Moose