Earl W. Stevick, Adapting and Writing Language Lessons… (1971)
“ The fifth assumption that underlies the modular approach is 'pluralism': 'If a thing is worth doing at all, it is worth doing in at least two ways.' In fact, it seems to be the case that if a word or a sound or a grammatical relationship is to be retained at all, it must be met with and studied from at least two points of of view. The coherent picture of structure afforded by a reference grammar, and the immediate linkage of individual qrammar points with individual instances in meaningful discourse, both should be available. ”
