Yes, Rene Levand is great - helped me out so much when I broke my arm from snowboarding. He has a website somewhere. You may want to google it.
Yes this trick is impromptu, so I think so.
I developed a version of it after watching several times, only reason being I desperately NEEDED to do magic, and there's not much you can do with 1 hand, when you already were use to 2. So I learned this trick and was very thankful for it.