What is preferred in the in-out effect: articulation locations or articulation movement direction?

Words whose consonant articulation locations move inward (from the front to the back of the mouth) are preferred over words with the opposite consonant articulation location direction, a phenomenon termed the in-out effect. Recently, an alternative explanation for the in-out effect has been proposed based on position-weighted consonant preferences instead of articulation location movement preferences. However, this explanation has only been...