I have come across it in the fifth episode of the tenth season of Friends. Here is the context: Friends
Monica: Hey Rach, the adoption agency needs letters of recommendation and we were wondering if you would write one for us.
Rachel: Of course, I'd be honored!
Chandler: Thanks!
Monica: Thank you!
(Joey looks at them, disappointed about their decision)
Joey: U-U-Um, I think there's been an oversight.
Chandler: Joey, we would've asked you, we just thought you wouldn't be interested.
Monica: Yeah, it's just we don't think of you as really being so much "with the words".
Does Monica think Joey isn't good with word or that he doesn't speak much?