They do have some support for local caching, but investigating that is on my todo list.
One big upside of this design is seo: your blog isn't on blog.domain.com, but wherever you want it on your main site.
[0]: https://www.contentful.com/ [1]: https://www.gatsbyjs.org/docs/gatsby-starters/
After countless hours supporting this system I decided to move over a couple of the content pages to Contentful (here's one example: https://issuu.com/m/success/madsounds). I didn't need to support anyone after making that move. As techies we tend to think things like Git are easy, but it's not (that's part of the reason we get paid the big bucks(
Also eventually basically all the company's CMS needs were moved over to Contentful. From my experience it scaled well for both small and medium-sized teams.
I use ghost for my personal site and I love it. (Not that I use multiple authors.)