An assumption will follow based on a few observations:
a) Thuls heavily rely on their "rawpaws", "blackhides" (their elite counterpart) are not a viable option for various reasons I won't bring up here. As a consequence, the first squad that is targeted by precautions ends up being "rawpaws".
b) The most useful precaution to single out a particular squad is "Worm Tongue". "Plague" chooses squads randomly (although it's incredibly useful when the player hasn't researched elites). "Worm Tongue" (which is misspelt in the game) is extremely effective, when successful.
Now, during several matches I could notice an odd repetition:
c) I would get "Worm Tongue", one after another.
There were times when I got three "Worm Tongues" in a row, playing against the same opponent in three different matches. The chance of having three consecutive "Worm Tongues" is 0.11^3 or about 0.1%.
I've had six "Worm Tongues" in the last eleven matches. The chance of having six "Worm Tongues" in eleven matches is 0.045703% (through a binomial distribution of a Bernoulli trial) — which is higher than Trefort's chance of finding a good looking girlfriend but generally, incredibly, low.
***
I now wonder: could it be that the random seed from which stem precautions success chances is somehow dependent on previous precautions successes. I believe that is a question to which only people with access to source code can provide an answer.
If precautions' random seed was actually saved and reused for successive precautions, or even modified according to already failed or succeeded precautions it would be possible to manipulate things so to have distinctively higher chances of succeeding a late "Worm Tongue" or any other precaution with low chances.