Maybe. It wasn't obvious what the behavior should be in the failure case. `_openDocument` will fail if any of the related files (i.e., stylesheets) fail to load. It's not clear that such a failure ought actually to prevent `_openDocument` from succeeding. 

On second thought, I think instead the `fail` handler should be removed and the `done` handler should be changed to an `always` handler. The thing I want to accomplish is to prevent `_onLoad` from completing before `_openDocument`, and not to make the function more strict.