I haven't read Strategy of Conflict, but I have read Robert Cialdini's book Influence: The Psychology of Persuasion, which Harry name-drops a couple of times and uses several techniques from. I'd guess that that's some of what you're seeing.

For future reference, though, it's considered polite to confine free-floating HPMoR discussion to the Methods threads, the most recent of which appears to be here. There have been a few Methods-related threads since, but all with narrower scope.