Would you consider Canvas, HTML5 Video, CSS Transitions and Animations, Application Cache, or WebSQL to be web-app-enabling features?[1] We were first to ship all of those. And they sure as heck aren't for documents primarily.
Editing a spec is a separate question from shipping order or general engineering priority. Not sure why you are conflating the two. Sounds like moving the goalposts.
I'd encourage to test IndexedDB in a WebKit nightly or in the Yosemite beta. It's still kind of buggy and not necessarily complete for final, but we'd love to hear about the key blocking issues from web developers.
[1] Yes, it seems like AppCache and WebSQL are both likely to be replaced by newer technologies, but I don't think that's relevant to whether sufficient priority has been placed on the area of webapps.