Yes! I linked to the recent Zodiac Killer cipher solution - https://youtu.be/iuNyQ44JYxM - over many years, many people observed patterns in the cipher, and tried to determine how likely it was that each pattern was nonrandom.

Eventually, they were inspired to try a particular combination of substitution and transposition based on a pattern people had observed at width 19. I think this observation was first made in 2015, and the cipher itself is from 1969.

So in the "Cryptodiagnosis" chapter Callimahos says ...

After finding a phenomenon - or what is thought to be a phenomenon - an evaluation should follow. It's not enough to say "I think the doublets are high." How many are there? Go count them. And, even more important, how many doublets are expected at random in a sample of this size?

Then, the team showed how that last question could be answered for the Zodiac killer ciphers with Monte Carlo sampling (i.e. modern computer methods).