Hand part of the bat?

[mcrowder]

There's nothing in the book about that. Maybe you should ask us what your actual question is - perhaps those "rules of thumb" you were taught have merit in certain situations. For example - Player A swings at a pitch and the pitch hits his hand. Dead ball strike (leading the layman to say "hand is part of the bat" when he sees this treated just like a foul ball. However - add R1 stealing 2nd to the same play, and make the ball go straight from hand to mitt, and you do not have similar treatments (if "the hand is part of the bat" in this case, it's a foul tip and the runner can advance at his risk - but that's not the ruling. Dead ball strike - runner back to 1B).

So what is the situation in which this came up or is a question?