Effect of number of decks

[QFIT]

The problem seems to be that, it's agreed that the chances for BJ on the first hand in a SD is higher than tha chances for a BJ for the first hand in 8D, but it's not clear that it stays higher on any given hand. How can this misunderstanding be cleared up?

What difference does it make whether you pull the cards off the top of the shoe or the middle? If there are fewer total decks, the chance of pulling a BJ is higher.