Patterns of suppletion in inflection revisited

Examining the distribution of suppletive stems over inflectional paradigms, a constraint on their complexity, call it Crossover Constraint, is shown to be untenable. There are paradigms, in some languages at some stage of their development, where suppletive distributions are maximally complex — like one stem of a verb being used for 1st Person Singular and 3rd Person Plural and another stem for all other person and number forms, which in terms of paradigm geometry is a crossover distribution. Rather than unceremoniously dumping this universal it is argued that constraints on states must be distinguished from constraints on transitions. There are two main routes to suppletion, the harnessing of distinct stems for one lexeme and the phonological separation of once unitary stems; their respective results are synchronically indistinguishable. When stems are combined, they will divide up paradigms in ways that follow morphological patterns, which outlaws crossovers, while phonological differentiations are under no obligation to respect morphological groundplans.