ch and sh as dual-function elements

[oshfdk]

The tail/no-tail distinction is not something extracted from the text itself. It is an independently observable physical property of the manuscript, otherwise of course it would be fatal. So I think it makes the permutation results not circular, unlike maybe many similar claims on the manuscript?

I'm not sure why this makes any difference, the text itself is also an observable physical property of the manuscript.

Let me try another example. Suppose we discover that the presence or absence of the tail on a star highly correlates with the sixth character of the corresponding paragraph. We shuffle the stars and paragraphs and this correspondence is gone. Does this mean anything?

For starters, if we assume purely random sequence of tails and paragraphs, given that there are hundreds of character positions in each paragraph there ought to be some of them which would appear to correlate more with the tails and some which would appear to correlate less, purely by chance. The question of how likely some statistical correspondence to appear by chance depends not only on the properties intrinsic to this correspondence, but also on the number of different statistical observations we make in total. With modern computational assets and machine learning algorithms it's possible to run analysis on billions of statistics and uncover a lot of seemingly interdependent features that do not correspond to any actual cause and effect. Proving that the result is not spurious just with shuffling the data is not possible in this case, I think.