Inconceivable kamma?

According to some translations, the acinteyya sutta (AN 4.77) states that “conjecturing about the precise workings of causality” / kamma leads to madness and vexation. Kamma is therefore among the 4 ‘inconceivable’ / unthinkable.

This seems pretty problematic! Theravāda lists 6 special /higher knowledges (chalabhiññā):

• “higher powers” (iddhi-vidhā), such as walking on water and through walls;

• “divine ear” (dibba-sota), clairaudience;

• “mind-penetrating knowledge” (ceto-pariya-ñāṇa), telepathy;

• “remembering one's former abodes” (pubbe-nivāsanussati), recalling one's own past lives;

• “divine eye” (dibba-cakkhu), knowing others' karmic destinations;

• “extinction of mental intoxicants” (āsavakkhaya).

Understanding causality is key in the awakening of the Buddha: prior awakening, one is expected to see causality in relation to one's past (seeing one's past lives) as well as to see causality in relation to others' future!

It's even more problematic that the Pāḷi doesn't at all suggest a translation akin to conjecturing about “the precise workings of” kamma:

Kammavipāko, bhikkhave, acinteyyo, na cintetabbo.

means

The fruit /consequence of an action, monks, is unthinkable and not to be thought of.

Not even the commentaries seem to suggest anything about “the precise workings of kamma”. So it would seem that translators struggle with the apparent… … … …