Powerful dialogue, weak adverbs...

"Does he still think I entered myself?"
"Well ... no, I don't think so ... not really," said Hermione awkwardly.
"What's that supposed to mean, not really?"
"Oh, Harry, isn't it obvious?" Hermione said despairingly. "He's jealous!"
"Jealous?" Harry said incredulously...
"Look," Hermione said patiently...
"Great," Harry said bitterly...
"I'm not telling him anything," Hermione said shortly...

From Harry Potter and the Goblet of Fire (underlining added)

The first thing I would point out from the above-quoted passage is that J.K. writes wonderful, natural dialogue. Not only does the interaction between the characters come alive thanks to the things she has them say, Rowling also creates subtle differences in the cadence and diction for each character so that we would probably know who was speaking even if she didn't include the "tags" that identifying the character.

For all her skill as a writer of dialogue, however, I am surprised at how much she seems to rely on the adverbs that describe how her character delivers a particular line. Surprised and, to be honest, a little bit irritated. There are days, like when I read the passage above from The Goblet, that I just want to go right through her books with a black marker and stroke out every such adverb.

Some friends have suggested that this over-use of adverbs is a "British" thing, something that J.K. would have learned early and never questioned.

Sure, maybe. But I wish she could have accepted that, when you write dialogue with the strength, creativity and realism that she does, when you use the words within the quotation marks (as well as the italics, ellipsises and other tools) so effectively to bring the speaking voice to life, you don't need to explain to your reader the emotion behind the line of dialogue: you don't need the adverbs.

It is not necessary, once you've had Hermione say "Oh, Harry, isn't it obvious?", to reinforce that Hermione delivers this line with despair in her voice. The despair is already there, in the "Oh," and the "Harry", and the question that follows.

It's funny. When I look back at the passage, presented in an abbreviated form as above, I realize that Rowling often delivers the emotion of the particular piece of dialogue with the first word the character speaks: "Well..." speaks of awkwardness; "Oh, Harry" speaks of despair; "Jealous?", which is a repetition of the last word Hermione said but with a strong question mark after it, fairly reeks of incredulity; "Look" captures a character trying to regroup, to exhibit patience; and "Great" in the context evokes bitterness.

The adverbs are unnecessary. They add nothing, except a faint odour of distrust, either of the reader's ability to understand what she is conveying or of the author's power to deliver effective dialogue.

I just wish that, by her fourth book, J.K. had learned to trust her reader ... and her self.