Collins et al. 2008 offers a principles-and-parameters-based analysis of an AAVE construction first described in Spears 1998, in which nominal phrases such as "John's ass" appear to have exactly the same denotation, and behavior with respect to familiar conditions on anaphora, as the possessor ["John," and similarly for pronominal possessors. Agreement, however, reflects not the properties of the possessor, but of the possessed nominal "ass," which belongs to a small, closed class of lexical items that behave in parallel fashion and which the authors call "mask" nominals. Collins and colleagues convincingly argue that the class of NPs consisting of possessors attached to mask nominals have the same syntactic structure as ordinary NPs displaying (pro)nominal possessors. In order to account for the split between anaphora and agreement, however, they are apparently forced to invoke a very complex derivational mechanism that includes a lowering rule, along with a number of other highly stipulative components, in order to encompass certain related constructions. I offer a far simpler and empirically more comprehensive alternative treatment in which mask nominals are nothing more than semantically parasitic heads, based on Kathol's (1999) dichotomy between AGR(eement) and INDEX specifications within head-driven phrase structure grammar representations. Collins and colleagues adduce what they take to be empirical arguments against such an approach, but these arguments are, as I show, all predicated on a basic technical misinterpretation of the nature of indices in the HPSG syntax/semantics interface, and thus have no force. Comparison of the two approaches is interesting not only in the context of the phenomenon described by Spears, but also in terms of broader, cross-framework issues--in particular, the question of whether or not movement and feature matching are merely two alternative, interconvertible ways of expressing linkages between structurally distant categories.