Wong quotes the "must win two bets on the next hand" success rate at 33%. My own calculations several years ago yielded 29% instead, rising to 31% if a 3:2 blackjack payoff is enough to succeed. Has anyone else calculated this percentage? I've been relying on my own hand-written note for years now, though I could probably find the software source I used around here if I looked. On to a newer question that arose over at BJInfo: What if you are allowed to double only on 9,10, or 11? If your first two cards aren't a pair or a 9,10, or 11, you're toast. It would nice to have a concise reference of success rates for Double any (DA2), Dbl 9,10,11 (D9) and Double 10,11 only (D10). To keep it simple, assume a player has only enough bankroll for two bets, eliminating any chance of three or more bet hands netting a two-bet win. Any volunteers?
I got 34% success rate if BJ pays 2-1 and the player can double on any two cards. .................................BlueLight
Am I right in thinking there are variations of D9 and D10 in which soft hands can/can't be considered as the lower total for doubling purposes? (And even if S19 and S20 can be doubled, they still might not let you treat a BJ as S21.) The reference might have to be a bit less concise than you would imagine, to handle all the permutations. [Actually, for ultra-completeness, there's another rule variation to consider: In a tournament a while ago, after I had spent an inordinate amount of time staring pensively at a pair of tens, the dealer enquired "Are you thinking about splitting those?". When I said yes, she explained that that would not be possible, as only cards of the exact same rank could be split, and I had JQ or whatever. That was the house rule for regular BJ, and had been carried into the tournament.]
I think that's the rule more often than not. Doubling would be restricted to hard 9,10,11. The ten split variation is also one I've seen before, and it would indeed make a noticeable difference in the result.
It's been over a year since I calculated the success rate of winning a doubled bet to be 34%. This was after I had over a 1/2 max bet lead going into the last hand and I bet 1/2 max bet thinking that whatever the next player bet I would win the round unless I got swung. The next player doubled a max bet and we both won the hand but I couldn't survive the 1.5 max bet swing. I don't remember if I considered eliminating the dealer of having a BJ for the 34% figure. I'll have to find my old notes. .............................BlueLight
