The proper (fractional) base used when cryptanalyzing runny messages was not such a strange idea. After all, napiers original log tables were conceived in term of using a base that was a small offset from 1. E.g. O.9999999
I you were 1920 trained math person, you be trained in such “strange” log tables – and such mechanical devices with vertical wooden “rods” bearing abacus like beads. The latter could compute, using the log basis in question.
So think! Tunny back to rods.
And from rods we get back to enigma/Hebern crytanalysis, and isomorph searching.
Of course, rods in enigma algebra are less about logs and more about relative automorphisms (as one computes conjugates).
But you see the eureka transitions.
Once turing and co figured that a discriminator could exist for a rotor set, now one can leap to its log (and an algebra of bulges).
What unclassified docs don’t say is the parallel analysis going on with quantum mechanics calculations, given the parallel effort going on with the ;mostly compartmentalized) atomic bomb making efforts (circa 1944).
Must have been fun to be thinking about the ” potential” of the electron cloud in a colossus tube/valve and that similar controlled electron (well neuron) flow used to accelerate a uranium chain reaction.