[l-jenkins]

High availability? Separating the editing/management interface from the live website allows you to quickly "re-publish" a site if something catastrophic happens to the hosting server. My organizations uses an enterprise CMS with the same concept. Our editing interface could be down, but the live sites are still up, and vice versa.

[ivopetkov]

That's correct. The interface though is not separated. The client software that is running on your server seamlessly connects to our cloud to provide you with the management tools needed. You can call it a proxy, but a much smarter one.