Check the rest of it out, and the discussion that inspired it.
I think that the place of Theory in Poli Sci is something more than intellectual history. At least, it should be. Ideas matter, or they MAY matter. Even the most doctrinaire Marxist historian thinks that the particular ideological superstructure erected around evolving economic relations matters for how the society functions. So, even if self-interest and materialist forces of weather, resources, and population movements are the driving forces behind history, ideas matter.
Grad students at Duke have to take at least one Theory course. Sometimes it works (students feel it is valuable), sometimes it doesn't. But I certainly find it useful to have a Theory group of faculty to talk to. (Two of our theory faculty are formally joint with our very good Philosophy Dept., btw, for those who think Political Theory is Philosophy, Poor Done). There are many questions that have troubled human societies for thousands of years. Sure, we have no definitive answer, but knowledge of the history of the arguments is something any educated person should have.
OUCH. Professor Munger.