Ember.rsvp.all Seems To Resolve Immediately

I'm really hoping that there's something dumb that I'm doing, but I can't seem to find it. I'm trying to use Ember.RSVP.all in the middle of a chain of promises. The example I have

Solution 1:

Answering based on a response to another question. It appears that while the $.ajax response is indeed "thenable", it is a jQuery deferred object, not a Promise. It's not clear to me why they don't play well together, but the solution is simply to convert the ajax call to a promise:

functiondelayAjax(delay) {
    returnPromise.resolve($.ajax({
        url: '/echo/json/',
        data: {
            json: '',
            delay: delay,
        }
    }));
}

With a working fiddle: http://jsfiddle.net/evilbuck/vqut9zy2/3/