Giddens challenged the schools of understanding human beings' social actions then, particularly targeting the tradition of interpretative sociology. The main critique he posed, as I understand, lies in the way how such interpretative sociology tradition tackles the "society" and interprets the order and integration of it. The focus placed on the "internalized value" and "social convention/norm" by the structuralism and functionalism and the efforts of interpreting human being's social actions against such "things", ignored the problem of the production/formation of these "things", and therefore disproportionately downplayed the social members' intention and capability to "produce" the social world during the reproduction dynamics. Proposed new "methods" (certainly not in a mandatory sense) for interpreting and studying social actions, Giddens, though he was very cautious in portraying the human society as a product of the social members intended efforts, attacked harshly the tradition of studying the human society as if there exists any mechanical laws or predetermined result in the society. Introducing the term "structuration", Giddens certainly attempted to re-find "agency" in social reproduction--and his argument leads to the rising importance of studying power and struggle to understand the human society and social actions. The "structure" of human society, he argued, was both result of and medium for social actions of human beings.
For Giddens this work may need to be so lengthy and detailed as he needed to well lay a battlefield and identify the target of his critique. For readers knowing enough about traditions and main schools of sociology, however, this book could be hundreds pages shorter without blurring its main ideas or weakening its main arguments.