In the version of the enigma cryptanalysis story given out by the UK for general consumption (which means its full of deceptions) we learn from the following the sense of the story:
In short, folks count repeats per amount of overlap,. comparing the count against the expected value of a count for a random case.
IN the more professional version of this story, less likely to be full of old-man-itis and military deception attempts, we learn that the story is far more about quantum experiments – and general experimental method.
https://yorkporc.wordpress.com/2012/09/29/expectation-from-inner-product/
Now, the “magic” of repeat rates is just a simple statistical statement – about repeated observations.
From this, we can get to the scoring system of banburismus – based on empirically accurate predictive expectations – that WHEN augmented with Bayesian logics, support measure theory and a rather pure approach of quantum entanglement theories about measurements in composite systems.