You’ll always win more money if you double down on hard 11 against any dealer’s upcard vs. hitting in all games, with one exception.
Aces regardless of what the dealer’s upcard is. Many players won’t split with a pair of 8s when the dealer’s upcard is a 9, 10.
A pair of 5s is also a hard 10 and you are always better off taking a one-or-more-card draw to a 10 than splitting the 5s.
This is a situation where most players chicken out and stand on their 12 because they fear busting.
Players mistakenly believe that totals 18 is a sure win, which is why they stand on soft 18.
Two-card 10 against any dealer’s upcard of 9 or less, which is why doubling down is your best strategy
You are playing an H17 game, the above three doubling strategy changes you should make vs. the same game with S17.
The range of dealer’s upcards where you should double down with soft 13 through 18 varies depending upon the number of decks.
The dealer will have a ten in the hole since there are four times as many ten-value cards in a deck.
A hard 15 and 16 are two of the worst hands in blackjack, especially when the dealer is showing a strong upcard.