@greysemanticist Ah, thank you 🙂 I got an e-mail sometime back which said that it can help you figure out how to restore your vision to 20/20 (the e-mail was in the spam folder, incidentally …) and that led me down several YouTube searches which led me to some videos but none of them were particularly useful.
So when I saw your post, I was intrigued. Will watch the video and give it a try and see how it goes …