...and here is some more ideas/works with my thumb/thumb base technology.
Double is taken and then angled for a moment while right hand demonstrates how spectator is to take card.
Upon turning wrist....thumb slides and re-aligns face card with deck. Because the card is angled, there is no need to register a switch. Also, optimal room for spectator to grab card at moment of the switch. The secret niche lies in knowing where to place double in thumb/first finger crease for perfect alignment.
There are many applications for this. Faced, finger spread visual, triple/quads, etc.
I have yet to find any works on this move. Always Now, RW