This concentration on power and its interactions/fluctuations and the things that power creates is atypical for documentarians. Indeed it is more typical to find such concerns in social theory, especially in the work of Michel Foucault (see here, here and here), rather than in tv documentaries.
This concern with the twisted paths of power and the people, ideas, places and events it, power, creates is perhaps most apparent in Curtis' stunning demolition of neo-conservativism & radical Islamic fundamentalism in his The Power of Nightmares.
The means by which the documentary makes its argument (constructs its discourse) is remarkable and the conclusions it comes to are shocking but its mode of address is actual rather quiet and conversational. Indeed, because the documentarian is only present as voice-over narration this is an even more quiet and self-effacing mode than that adopted my Nick Broomfield. This seemingly neutral presentation is a part of the great strength of Curtis' approach.