Apple Final Cut Pro 7 - Manual (Page 1003)

When you do this kind of edit, watch out for the beginnings and endings of words.
Sometimes people run words together if they speak quickly. If you’re replacing a word
in clip 1 with the same word from clip 2, make sure the sound that comes before the new
word in clip 2 is the same as the sound that comes before the word it’s replacing in clip
1.
Cut away to another image to smooth cuts in dialogue
If you need to remove a word or phrase from someone’s speech, you can use a cutaway
shot or B-roll footage at the same point. This allows you to change the audio without
viewers noticing an obvious jump cut.
One reason shots of the interviewer are included in documentary-style programs is to
give the editor the freedom to edit the speaker’s dialogue without introducing a jump
cut in the picture. That way, if the person on camera says the same thing twice, you can
cut it out without the audience’s knowing and make the subject sound better.
You can also do this in narrative programs. If you decide to rearrange an actor’s lines by
adding or removing dialogue, you can cut to a reaction shot of the person who’s listening
to smooth your changes to the speaker’s audio.
Change the pace of off-camera dialogue
As long as the speaker is off camera, you can make other dialogue changes as well. For
example, you can easily change the pacing of what’s being said, making the sentence
sound more or less dramatic. The key is to have footage you can cut away to that will
seem plausible. An audience shot or another actor listening are two examples of plausible
cutaway shots.
Remember, if you create any gaps as a result of editing your audio, fill them in with room
tone.
Use the video from one take with the audio from another
Sometimes you’ll have multiple takes of a particular shot, each with something good in
it. For example, suppose you have a series of takes of an actor saying, “Wow! That’s a big
piece of pie!”
1003 Chapter 61 Tips for Better Audio