It is common to say that something is good in theory but not in practice. I always want to say, then it is not such a good theory, is it? To be good in theory but not in practice posits a relation between theory and practice that places theory prior to practice, both methodologically and normatively, as if theory is a terrain unto itself. The conventional image of the relation between the two is first theory, then practice. You have an idea, then act on it. In legal academia you theorize, then try to get some practitioner to put it into practice. To be more exact, you 'read law review articles, then write more law review articles. The closest most legal academics come to practice is teaching-their students, most of whom will practice, being regarded by many as an occupational hazard to their theorizing.
Catharine A. MacKinnon,
From Practice to Theory, or What is a White Woman Anyway?,
Yale J.L. & Feminism
Available at: https://digitalcommons.law.yale.edu/yjlf/vol4/iss1/3