Hotkeys

There following keyboard commands are only applicable from within the check spelling dialog:

CapsLock-K: Read the misppelled word on first press. Spell it on second press. Phonetically spell it on third press.
CapsLock-I: Read the line containing the misspelled word.

Usage

With a document open with gedit, press F7 to bring up the check spelling dialog.
If nothing happens, that means you have no misspelled or unrecognized words in your document
If the dialog does come up, you'll be read the line in the document that contains the first misspelled word, the misspelled word will be spelled out for you, and the first suggested spelling will be read. The text entry field that allows you to replace the word will have focus.
To get to the table of suggested spellings, hit Tab twice.

If there's no misspelled words and you try to check spelling, it just does nothing. The status bar DOES say that there are no misspelled words. This is likely a bug in gail.
When the window first opens, the phrase "context information" is not said before it reads the context line. This happens because the caret change event that we listen for to cue the "context information" phrase happens before the check spelling dialog gets focus, and the logic that has LSR read the phrase asks whether the check spelling dialog is up or not.
Under Ubuntu, document statistics dialog will loop infinitely when the dialog is read. We can't duplicate this under fedora, so we're not going to try to chase it down.