As indicated in the video, the first few minutes are me going over the when/why to use Shared Layouts. If you want to read that (below) instead, skip to 4:00 in the video.

Summary of when/why to use shared layouts:

• Use Shared layouts when layout inheritance isn’t enough. Example: You want some posts to have one layout and others to have a different layout
• When you want to export a Template to use on a different WordPress installation either yourself or another Headway user
• Or just because. I personally prefer using Shared Layouts over cloning. There is actually less data stored in the database and such this way.

Summary of things to know:

• You can’t (yet) assign Shared layouts (or any layouts) to all posts in a specific category
• You can’t (yet) mass-assign Shared layouts to posts/pages