This is a nice Larry Jordan piece about the precision editor.
The precision editor allows you to see edit points in detail including unused frames before and after your edit point.
However, the most interesting point he makes is an off-hand comment about adding black frames to help with the rhythm of the dialogue.
Larry adds a couple of black frames to create a short break between sentences. This helps hide the edit and make the dialogue flow more naturally.
Larry adds that he will cover over the black frames with B-Roll or cutaways later.
This is probably one of the most important pieces of edit advice you can give:
Sort out the audio first and make sure everything flows nicely. You can easily make the video look nice later.