I'm new (very new--2 days in) to cardistry and am going through Genesis V1. In the video Jikh says the Charlier cut begins with your index finger pulling half the deck down into your hand and then pushing with the same finger. I've also seen where people use their thumb to let half the deck drop and then push with the index finger. Is one way correct? (By "correct" I mean doing it one way will make cardistry life difficult down the road)