I'm with Nicole. I always build my storyboard in Storyline (for elearning at least) so I can use it as a prototype.
Here's my steps:
1. I can get approval on a design right up front by building a few slides with the look and feel and colors I want. Maybe some additional colors for stakeholders to choose from. I insert some of the content as well.
2. I build more slides with content. Not only can the SMEs check the flow, but I think it cuts down on my work. I don't have to copy, paste and format a Storyboard in Word. I do it all in one place.
3. I can make in-line changes when talking to SMEs.
4. I publish to Word when I want SMEs to have full editing capabilities avoiding the separate Storyboard again.
5. Also, I use publishing to Word for developing job aids or guides.