Damn bruh you are extra wrong and not even close to how the trick was doneOK, so I got the heart trick. Thought is definitely in on it. When Blaine separates out the 10 cards, he then puts them on top of the main deck before handing the smaller stack to Thought. Notice the cards in the main deck are face down.
This does 2 things: 1. gives illusion that there are 10 cards and 2. allows David to slip in more than 10 cards. Notice the way he asks Thought to count the cards when he gets them. The initial 10 cards are face up. he then asks Thought to turn them face down and add them to the bottom of the card stack when counting (Thought does an admirable job of acting by messing up initially). So when he reaches the first card that's face down in the stack, it looks like he's counted only ten cards. But there are indeed more than 10 cards.

Also no one was in on the trick. I use to card tricks as a kid and you were not even close fam
