I recently split up a large storyboard for the first time, and I couldn’t believe how easy it was. The Editor->’Refactor to Storyboard’ tool actually works perfectly.
Now my Storyboard doesn’t take 15 seconds to load when I jump between files, it makes it easier to work on, merge, etc.
Just wanted to share — and encourage anyone who is afraid of splitting up a big Main.storyboard to not be. The built in tool works perfectly, and everything is better!