The Blackjack dealer is an interesting topic. Unraveling him is one of the big secrets of Blackjack . He has nothing to do with the way the Blackjack hand or game will unfold. After all he has very set instructions on what to do and has zero say in what happens. He will do what you say and follow your orders and when it comes to his hand he has no decision either.
But you still want a Blackjack dealer who you have a nice rapport with. A dealer who has a sense of humor and goes with the flow of the game. In fact a dealer is responsible for maintaining the atmosphere around the table. You don’t want someone who is going to turn the blackjack table into a morgue or a library. It's ok if he is not your friend and fine if he is neutral but you want him not to be an enemy. That is very bad Blackjack strategy.
The best blackjack dealers are those who act seamlessly and just let the hands progress. Also helps if there is a steady amount of winning hands the players are getting. To alienate the players get a five when on 16 or 3-4-5-9 to get 21 and defeat everyone at the table.
It is also important that the blackjack dealer makes everyone around the table comfortable. No one wants to feel as though they are playing blackjack with their parent or the school principal.