In my personal experience. No, with skill (perhaps natural born talent) people can have 100% complete controle over their emotions. I would not recommend developing this skill and rely on it, cause I feel it has back fired on me hard. To the point I no longer trust my emotions, i.e. I don't know if I'm actually feeling an emotion, or if I've subconsiously decided to feel the emotion.
I suppose some people will tell you that what I describe isn't controling your emotions, only surpressing them. But I disagree.