
Question about the Ben Blau "Unfazed" card trick
I've been watching this and practicing it with numbered playing cards to try and figure out how it works out. I've been using 2-6 in black and 2-6 in red instead of symbols. I get everything so far except the final decision point with the two stacks of two cards. Following the routine along (I think) exactly, I keep getting screwed up at the end trying to mimic the last choice.
At 7:45, he makes a move with the cards in his hand but I can't quite understand what he's doing with it. It looks like he takes the top two and puts them below the bottom two but I can't quite make it out. However, I'm not sure that matters because in Eugene Burger's version (https://www.youtube.com/watch?v=dmsiaV1TeHE) he doesn't do that (4:15 mark).
I'm also trying to understand the configuration the cards are supposed to be in in the two pairs at the end. In both Blau and Burger's videos, the spectator swapped one side and then the top two cards are the match. So if the expected configuration of the piles is XY and YX, that makes sense.
I'm wondering if the choice the spectator makes drives how you pick up the last two cards. Assume XY YX are the two piles...if they swap one side you take the top card. If they pick top or bottom you end up with YY XX so you just take either side pile.