Hi there
Your post is a bit confusing. Here's why. You are describing that you like to use this process. So it's a process you have apparently already sorted. But then you go on to ask if it's described anywhere. Why would you need it described if you have already sorted it? 
Actually, your process seems backwards from the normal way we see folks work with Captivate. Normally we record the video portion as a first step, then come in later and add the narration.
Cheers... Rick 