Thanks for the reply. I was hoping that it would be a great question for you, but...
This is one of my favorite places, so I will wait for a response here from Robert Johnston or any other user who has the time to contribute to this topic. If no other responses, I will draw my own scenario based on the original details supplied and on what I see by actually carrying out the procedure.
Basically it allows you to edit a lower resolution file that requires much less computer resources than required for AVCHD. On a less powerful computer PE7 will stutter playing back AVCHD files from the timeline making it difficult to edit, especially when effects are added. The solution is to render the timeline... this converts the AVCHD files to HD MPEG2 files which are less processor intensive... but this takes time and you need to keep rendering when you make an edit. Using the proxy you can view the video/effect without rendering.
Thanks for the reply.
I am with you about editng preview file (proxy) instead of the original AVCHD HD1080i or HDV HD 1080i. But, I went off course with your comment:
"Using the proxy you can view the video/effect without rendering" since you do not see the preview file until after you have rendered your edit of the Timeline.
Perhaps my understanding of that will answer the question that I asked about the benefits of using the proxy procedure if the workflow is just import, no edit, export.
"Using the proxy you can view the video/effect without rendering"
You can view the effects applied to a clip without rendering... if you apply the effect to a low resolution clip the processor will be able to play it back smoothly... so without the need to render. If you apply the same effect to a high resolution clip you would need to render the clip to see it play back smoothly.