In my head, I'd built the classic force up to be so much more difficult than it is. The reason for that was Paul Green's "Classic Force" DVD. He goes into so much detail about how to move the cards towards the participant's hand, what you need to look for in their motion etc., etc. Then I saw Simon Lovell's "The Madness Behind the Methods" (yes, a Magic Makers product, but it's good). His description of the classic force made it so simple for me I literally never miss. I wouldn't challenge people on it, like "Go on, pick a card, I bet I'll make you pick the nine of spades...", but for practical purposes in the context of a routine it's perfect.