How to decipher the Wegener cipher?

Question

Cryptography

Help deciphering the Wegener cipher
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_ - is a character.
Key length 4 characters

Answer 1

4 characters in the key is very small, it's 34 to the power of 4 brute force options
i.e. it is enough to write a quick function for determining the correctness of the text (for example, to check for the presence of an existing word or part of it, syllables, prepositions, roots) and run through the entire range by brute force, calling this function for each combination.
More cleverly - to use the knowledge of the number of characters in the key, i.e. it is enough to sort through one character at a time and consider only 33 options, but when only every 4th character is visible from the source text. Those. it is necessary to improve the function of determining the correctness of the text so that it can at least give the probability that this particular character gives a text similar to the truth (for example, the frequency of occurrence of a particular letter at a certain position plus the length of words separated by a space, etc.) then instead of enumeration of key values ​​from 1 to 33, you need to determine these values ​​in order through the probability of being exactly this character correct, and start enumeration with values ​​with a higher probability, which means that the answer with a high probability will be found at the beginning of the enumeration and not 33,33,33,33.
Any improvement in the algorithm revolves around some knowledge of the encrypted message.