What is the dual systems theory in sociology?

Particularly concerning gender-based division of labor in the United States, the dual-systems theory "argues for the importance of both patriarchy and capitalist rationality, but acknowledge that the presence of dual-causal dynamics leads to indeterminate predictions of actual sex types" (Women and Work, Dubeck and Borman, 1996 p. 88). There is also another view point that speaks to the exclusion of women from "good occupations" as a way to keep them from obtaining the jobs that men typically have, because this would restrict the potential for "competition" for these jobs and keep men in power (Dubeck and Borman, 1996, p. 88).