Yeah, so the reason VR works is that it controls the entire scene. The light being projected towards your eyes is from a consistent focal plane -- the light comes from a flat surface located exactly N inches away from your eyes. That means you can focus sharply on it.

AR is a very different beast. In the real world, your focus is usually several feet away, or sometimes across the room. Your focus also changes almost instantly. Yet AR still needs to project light toward your eye from exactly N inches away.

You can simulate this: Find some glasses and put some black tape over part of the lens. You'll notice the tape doesn't appear sharp and crisp. It's a blur.

(Or just close one eye and put a finger close to your other, and look out in the distance.)

I'm not sure AR has any hope of rendering text in a readable way. It'd be like writing some letters on your finger, then putting it up to your eye while looking out in the distance. Even if the letters glow, so that they're a light source, you still can't read it at all.