Fear, anger and hatred are pretty broad terms. Just because they use these things to fuel their power and aggression, doesn't necessarily indicate they feel them in the traditional sense.

Now, as funny as a jowel-jiggling, tape-destroying, 'FUCK THE BASTARDS' Nixonian Palpatine is, as evidenced by Nixon himself, it's not the most fortuitous or perpetuating way to go about things. If paranoia and hatred become too large a part of your social or political makeup, the less influence you can maintain; it's why the crazier of Hitler's Nazi rabble were kept quiet until the end of WWII, it's why people like George Wallace and the segregationists in the 50s and 60s fell apart, and it's why the Tea Party-types of today don't get much traction beyond angry fist-shaking get-togethers. Fire and brimstone is an awfully short high, however passionate it is at first.

Now, using fear, hatred and anger in your arsenal, as the Sith do, is what makes them powerful. Like, Palpatine, they might not particularly believe in the state of bipartisanship, but if he keeps the facade of the level-headed, wartime pragmatist going, he emboldens those who follow him, and can more easily plant the seeds of distrust and hate against those who stand against him. If a mean person tells you not to like someone or something, for whatever reason, it's not as influential, at least at first; they're making more of an ass of themselves. But, if an authority figure, someone who exudes trust and responsibility and fairness, tells you not to like someone or something, you're more likely to take it at face value.

I'd like to think Dooku genuinely believed in the cause of the Confederacy, and saw bringing down the Republic as more important than slaying all the Jedi; he respected Yoda, as any good student respects a wise teacher. That respect doesn't fade, despite differing viewpoints, even to such a drastic degree. I don't think Yoda had to cast any magic spells on anyone to 'calm' him (that honestly sounds less Jedi and more tired babysitter, to me), but he presented his belief, and his point of view to Dooku. Dooku, seduced by the dark side, disagreed - to prove a point when their duel wasn't getting anywhere, he played onto Yoda's fears by turning the threat toward the incapacitated Anakin and Obi-Wan, as to make a quick getaway. There's the power of the Sith; not feeling fear, but using it against others. The Jedi way doesn't do that, and doesn't need to.