According to these consonant assimilation rules, the letters г and к form a voiced/voiceless pair, and the final consonant in the cluster voices or devoices the preceding consonant.
If these rules apply, then shouldn't the 'г' in "мягкий" be assimilated into another 'к'? Why is it pronounced like an 'х' instead (mʲæxʲkʲɪj
)?