Interesting question. I have a firm rule. I only count the cards after the dealer has exposed them. For example, if a person flashes his cards because he wins a side bet, I do not count them, but if he doubles down and places his cards face up, I then count them. I always wait, even if I see the cards, for the cards to be finally turned up on the table. This is my personal way, just discipline. The only exception I make is in pitch, when I am considering an insurance play, I will then take any information that comes my way.
--Mayor