There is a good reason to give a client only a sound file on the first edit during commercial video post-production, if there is no scripted voiceover. They get to hear the storyline and really get a sense of the message they are sending, without the distractions of inserts and cut-aways. I do it with some of my clients for that very reason.
I have a client who trusts me to add good cut-aways and graphics later. I provide an MP3 file on the first edit. He says transcribes the story and even reads it out loud. He wants to know how it sounds from his voice and from the voice of those in the video to verify that the story is good. I like that sort of dedication to making the best product possible.
Not every client wants to listen to an audio file first. But, if you can get them to appreciate that part of the process, you can end up with a stronger finished product at the end.