A very different approach to the opposite phenomena is the morphological approach of Baerman (2007), in which inversions are simply due to explicit morphological rules. Since these rules are totally arbitrary and extremely powerful, we are not adopting such a solution; Furthermore, such an approach is unclear on how to handle the omission of subject markers. It should probably apply before any morphological rule works inversion. We will come back to the omission at the end of this sub-part. According to Lillo-Martin (1986), null arguments with simple verbs have different syntactic behaviour than concurring verbs, and the licensing mechanisms for these two types of arguments are therefore different. In this analysis, the agreement itself identifies the null arguments displayed with consistent verbs. Such a proposal depends decisively on the existence of a class of verbs consistent with syntactic consequences. Bahan et al. (2000) argue, unlike Lillo-Martin, that the null arguments of both types of verbs are licensed by agreement, but that it is used only as non-manual agreements with simple verbs. Although this proposal is different from Lillo-Martin`s in terms of the licensing of null arguments and their syntactic type, it depends on the notion of a morpho-syntaxic agreement. See Koulidobrova (2010) for another view of the licensing of NULL arguments in ASL and the relationship between null arguments and the directionality of the verb.
Again, none of this is relevant to the difference between BAVs and LVAs. Kalin (2015) analyzes conventional neo-Aramaic inversions in the form of a difference in the movement of the verb: in the reverse scheme, v moves on the subject to fault in the imperfect; Assuming that Agree applies to the phase level, it is done after the head movement and therefore targets the external argument, while T corresponds to the object. In perfection, on the other hand, v targets the object, while T corresponds to the external argument. From a technical point of view, this could also work for RAV/BAV asymmetry, but as there is no evidence of asymmetry in the movement of the verb between the two types of SL verbs (both types of verbs behave in the same way.