मृदु-मध्य- अधिमात्रत्वात् ततः अपि विशेषः।।
Mṛdu-madhya-adhimātratvāt tataḥ api viśesah
Even among them there is difference based on their mild, middling and excessive efforts
Mṛdu-madhya-adhimātratvāt is a compound and is in the fifth case. The fifth case is used here in the sense ‘because of/due to’. The component words mean mṛdu mild, madhya middling, and adhimātratva excessive. Mṛdu-madhya-adhimātratvāt means due to mild, middling and excessive (efforts).
Tataḥ is indeclinable word formed from tat with a suffix tas. Tataḥ means ‘among them’. This pronoun refers to the practitioner mentioned in sūtra 1-21.
Api is another indeclinable word meaning ‘even’.
Viśeṣah, formed from the verb śiṣ with prefix vi and suffix a means ‘difference’. The translation above is based on this analysis of word formation.