I find myself (to my joy) cited in it:
Try getting it right, Creighton. Don’t attribute to me things I haven’t said.
I have not proposed that “these numbers” were written in any manner whatsoever at the quarry. No such statement appears in the post cited:
—and I have never suggested that the numbers were written at the quarry.
I did not “infer” ad hoc “that a mistake was made at some point during the production of the lithographic block”. My point was precise: that where two lithographs based on one original differ (and we don’t have the original), then uncertainty due to this conflict of evidence remains:
“Where lithographs A′ and A″ differ and the original A is missing, doubt regarding what was in A is irreducible.”
If the lithographs differ, then one (at least) of them is erroneous and our knowledge of the original is compromised.
I suggest that readers look very carefully at the material Creighton cites in support of his claims.