re: Poker & Player sit out question
Typically cards are dealt to sitters in tournaments since blinds are forcibly posted and the player may show up before his first action gets to him. In the live poker rooms I've played, they're not usually dealt and when the sitter returns they have to wait until next hand (and then either wait or post blinds if they missed them).
As to probabilities and getting other people's cards, honestly that's results-oriented rubbish, although I understand the human nature to want to attach significance to it. The whole concept of random distribution makes it irrelevant. It's the same concept when counting outs regardless of how many people are dealt in, because all you know are your cards -- so you count total unknown cards regardless of whether they're still in the deck or not. Same thing when people get upset over static vs dynamic shuffle online -- it doesn't matter or change probabilities because you didn't know the outcome to begin with. Or people who fold a trash hand that flops the nuts and get upset about it or change future decisions based on that. Or rabbit hunt for any more than pure entertainment value.
They're all pointless, results-oriented exercises that you should really avoid distracting yourself with.