Regular Metathesis in Batanic (Northern Philippines)?

Regular metathesis has been reported from a number of languages and language families, but appears to be particularly common in Austronesian. This paper focuses on a single close-knit subgroup of Philippine languages represented primarily by one of its members, and shows that regular metathesis may have occurred in its immediate common ancestor, Proto-Batanic. The particular interest of this case is in showing how difficult it can sometimes be to distinguish genuine metathesis from what has been called "pseudo-metathesis" (apparent segmental transposition resulting from syncope and epenthesis in either order). Arguments can be assembled supporting both positions for this group of languages—either they show a rare type of metathesis, or they underwent syncope and subsequent addition of an initial vowel. Since neither position is free from problems, the matter must be considered indeterminate at this point. Finally, the Batanic case is particularly puzzling, as it is paralleled by a strikingly similar change in Kapampangan that must have been historically independent.