This article examines the limited productivity of a minimally schematic Icelandic microclass, originally containing bók ‘book’, bót ‘patch’, brók ‘trousers’, nót ‘fishing net’, and rót ‘root’ only. Productivity is betrayed by the addition of feminine blók ‘nonentity’ and forms of neuter kók ‘Coke™’. While plural nominative/accusative blækur and kækur speak to the productivity of the microclass specifically, doublet forms in both paradigms follow multiple inflection classes. Some are of the opinion that plural kækur belies real language use, as it is only used for humorous effect. The current paper applies a usage-based cognitive analysis to the relevant data with two objectives. First, to account for graded membership in the microclass as a function of limited productivity. Secondly, to demonstrate that innovative kækur and blækur are deduced by identical means. It is concluded that productivity is a property of language use, which is posited as a function of analogy.