actually I witnessed a dealer spin 7 five times straight. They do get into sections and are promptly reminded to get out. As for card counting; yes you increase the odds in your favour BUT only 2%. 49% the house 51% the player.That is as good as it gets, I've worked in casinos.Btw card counters are easily spotted-fair to say it is the only way to beat the house.
cheers,
walt.