Workflow for narration with closed captioning?

I've been finding it very useful to write out my narration in slide notes, and then use text-to-speech to generate temporary narration for review. The plan is that once the content has been reviewed for technical accuracy and approved, I'll go back and record the real narration.

For that part, since I already have the text divided into chunks in the slide notes, it would be really great to have a way to record each "line" separately, because that would allow Captivate to figure out the right start/stop times for each caption automatically, like it does with text-to-speech. However, I haven't found a way to do this, so I'm starting to think my only option will be to record the narration as one long clip per slide, and then manually reset the timing for each caption (or ditching the closed captions for a mess of overlapping caption boxes, but then the user won't have a convenient button for turning them off/on), which I am really not looking forward to.

So, before I resign myself to that, I just wanted to check: is there anything I'm missing that will let me define the captions first, then record text for each caption? If not, do most people just manually set the timing for every caption (or ignore them altogether)?

Thanks to anyone who can help!