>convert each letter to a number, add up the numbers that make each sentence...The end result is sufficiently transformed that copyright no longer applies
the problem with this as an example is that copyright would not apply to this transformative work, not the original author's copyright nor your new authorship because this transformative work contains no creative human expression (unless the original book was designed to add up to some fortune cookie, of course, in which case you have not transformed it)
A nuttier, chewier example would be retelling a litigious story like Moana ("consider the copyright, across all these leaves... make way!"), from the pig's perspective or something, and seeing what would fly and what wouldn't.
the problem with this as an example is that copyright would not apply to this transformative work, not the original author's copyright nor your new authorship because this transformative work contains no creative human expression (unless the original book was designed to add up to some fortune cookie, of course, in which case you have not transformed it)
A nuttier, chewier example would be retelling a litigious story like Moana ("consider the copyright, across all these leaves... make way!"), from the pig's perspective or something, and seeing what would fly and what wouldn't.