I've never seen it and i dont know what it looks like, but I'm not sure i understand the point to learning flashy double lifts (enless you are using it as proof that there is in fact only one card for example the Ginastaire Double) other than that there is no reason to practice a tough double because you want it to look just like you are turning over a normal card. I dont think ive ever seen someone turn over one card in a really flashy way.