That's a similar technique to what I'm doing; I use language-agnostic templates (mustache) so that I can do a full server side render, and then my Backbone app initializes with bootstrapped data. This way, we can progressively enhance the site and have a quick page load and at the same time build a single page Backbone app.
I've been using hogan.js to compile mustache templates to JavaScript functions on the server-side and write them to a js file that is then served to the browser:
