I loved the bit in Plagues of Night
where the Tzenkethi Autarch takes us through his mental process of manipulating absolutely everything and everyone around him to his own wishes. He predicts and plans and manipulates them to get them to stage preemptive attacks against Federation colonies, and the best part is when he admits to himself that he basically does this purely for fun and to fill the time. He has no greater purpose in doing this than to screw with them, because he knows he can. And it works. I guess that's why he's the Autarch.
And that ties into what you were saying about predicting behaviour, Nasat
. This kind of manipulation works well among the Tzenkethi themselves, because it is simply inherent in their culture. The Autarch does the manipulating because that's what the Autarch does, and the Tzelnira get manipulated because that's what the Tzelnira are there for. But as you said, it seems that when they try to apply those same techniques outside of the Coalition, it doesn't work quite as smoothly.