MovieCaptioner keeps repeating a segment of the movie until you are done typing what you hear.
Just hit the Return key and it will save your caption and automatically advance to the next few seconds of the movie, allowing you to zip through your captioning tasks in no time flat.
And, if you use MacSpeech Dictate, you can just speak the captions and it will type if for you right into the MovCaptioner interface, the absolute easiest way to create captions for your videos!