It is a well known observation that phonological processes which apply to short segments frequently fail to apply to corresponding long ("geminate") segments. For example, post-vocalic spirantization of velar stops in Tigrinya yields [?a-xalib] 'dogs' (cf. [k~lbi] 'dog'), but [f~kk~~] 'boasts', not [f~xk~~] nor [f~xx~r~] (Kenstowicz 1982).49 This phenomenon of geminate "inalterability" or "blockage" has been the subject of a number of proposals within the framework of Autosegmental Phonology, most influentially Hayes 1986 and Schein & Steriade 1986.50 Subsequent research, however, has revealed that these proposals make incorrect predictions as to the class of processes which display inalterability (see Inkelas & Cho 1993). As Churma 1988 observes, geminate inalterability holds true as a universally inviolable condition only in the domain of lenition phenomena, a generalization which the classic inalterability approaches fail to capture. Moreover, as Elmedlaoui 1993 notes, within the domain of lenition phenomena, the classic approaches are insufficiently restrictive: they fail to rule out processes which specifically target geminates for lenition, e.g. Ikkl ... *[xx), or which convert an underlying singleton to a lenited geminate, e.g. IkI ... *[xx); and they fail to draw a connection between inalterability and the general markedness of "weaker" (i.e. continuant and voiced (obstruent» geminates, whether derived via some lenition process or present underlyingly.