the careful articulation ... in a single sweeping movement of muted, respectful triumph

[Coffee Break]

I read this expression, "the careful articulation ... in a single sweeping movement of muted, respectful triumph", but am finding it difficult to understand it. Could you please let me know what it means? Here is the excerpt:

One afternoon, I saw that a group of journalists had gathered in a cluster in the lobby. From a distance and over their heads and outstretched devices, I saw Kees, standing at the center. He was gesticulating to the assembled crowd and I saw the conviction with which he relayed his message, everything was calculated, from the way he looked into the camera to the way he made eye contact with the individual
journalists, the careful articulation as he brought his thumb and index finger together, then splayed the fingers out in a single sweeping movement of muted, respectful triumph.

- Katie Kitamura, Intimacies, Chapter 16

This is a novel published in 2021 in the United States of America. The protagonist is an interpreter working at the International Criminal Court at The Hague. Now she is looking at the situation where the case against the former president--who stood accused of having committed war crimes--has been dismissed. So the defense lawyer, Kees, is giving an interview to the journalist regarding the dismissed case.

In this part, I wonder what these expressions mean.
By "the careful articulation," would it be correct to understand that he pronounced syllables clearly (=articulated) in a careful manner...?

And then I wonder what gesture he did with his fingers in "a single sweeping movement of muted, respectful triumph."
Perhaps it's because I don't know how English speakers express triumph with fingers, but I just cannot imagine what he did with his fingers, so I wanted to ask you.

 

[Tarheel]

He's feeling triumphant about something. (He has achieved something or won something.)

As for the gesture, I don't think the reader is expected to understand that phrase, which is why the gesture is described so carefully.

I wouldn't overanalyze it. I would simply move on.

 

[jutfrank]

By "the careful articulation," would it be correct to understand that he pronounced syllables clearly (=articulated) in a careful manner...?

Yes.

And then I wonder what gesture he did with his fingers in "a single sweeping movement of muted, respectful triumph."

Yes, you're right to try to imagine the scene, but we can't do it for you. The hand motion is described pretty precisely, so if you still find it hard to picture, just imagine him speaking carefully, confidently, and articulately, and gesticulating in a complementary way. Think also about how he feels as he's talking and the impression he's making on his listeners. That's all you have to do as a reader.

 

[Coffee Break]

@Tarheel and @jutfrank,

Thank you very much for the explanations.
So it is not a fixed gesture of English speakers! It is some personal gesture made by Kees, which is why the gesture is described in a detailed manner.

He pronounced the words carefully and distinctly (=careful articulation) while he brought his two fingers together than splayed them in a sweeping motion, expressing a non-verbal, and respectful (I guess the gesture was not offensive, thus respectful) triumph and victory.

I truly appreciate your help.