Interesting story that pushes the state of the art, sounds like a lot more work needed to establish the usefulness of this kind of drive, seems a little like some of the technologies envisioned by Nicholai Tesla, we don’t really know if they would have worked or not, and probably only he had enough faith to have succeeded, had his funding not been removed, but it gave us the inspiration to later create technologies with similar outcomes, like the internet, and capturing the energy of the sun.