So much for the choice of whether to hit or stand in a particular situation, but how about the decision on whether to double down or not? In some cases the decision will be obviously indicated by our previous calculations, as in the following example.
Suppose we have (A,6) v dealer 5. (Any two card total of hard 10 or 11 would illustrate the situation equally well against the dealer's up card of 5.) We know three things:
1. We want to draw another card, it having already been determined that drawing is preferable to standing with soft 17.
2. We won't want a subsequent card no matter what we draw (for instance, drawing to (A,6,5) would be about 7% worse than standing).
Our overall expectation from drawing one card is positive that is, we have the advantage.
3. Hence the decision is clear; by doubling down we make twice as much money as by conducting an un doubled draw.
Double-down situations were covered in the sections on hard totals and soft totals, but just to put it into one place, let's review when to double down:
- Double on 11 against any dealer's up-card except an Ace.
- Double on 10 against any dealer's up-card except 10 or Ace.
- Double on 9 when the dealer shows 3, 4, 5, or 6.
- Double on soft 13 or soft 14 when the dealer shows 5 or 6.
- Double on soft 15 or 16 when the dealer shows 4, 5, or 6.
Double on soft 17 or soft 18 when the dealer shows 3, 4, 5, or 6.