You want to avoid betting behind, as you are not allowed to double or split on those hands. Also tables get very full, and I have often found the game "cancelled" owing to a technical error when a card is not scanned properly. It always seems to be the case that the dealer has a 5 or a 6 when this happens! I have heard of people banned when they have staked as little as £200 with counts of +3 or so.