'Double up blackjack' - outcome of my 20 vs dealer 10

DSchles

Well-Known Member
#2
jacblacc911 said:
What percentage of the time/how often does my inital 2 card total of 20 win vs a dealer 10? And how often does it push? Assume neutral deck.
Number of decks?? If 6, then 78.0% for T,T and 77.8% for A,9. This excludes pushes and is for 100 win or lose decisions. Sorry, not sure about pushes.

Don
 
#3
Yes, it is 6 decks.
In this BJ variant, using the example of a 2 card total of 20, I have the option of placing the ‘double up wager’ (equal to my original bet - pays 1/1). If however the dealer makes 20, I lose the double up wager and push the original.
So for every situation of a 2 card 20 vs 10, I stand to win 2 units (original 1 unit, double up wager 1 unit) if dealer makes 19 or less or lose 1 unit if the dealer makes 20.
 

DSchles

Well-Known Member
#4
"Yes, it is 6 decks."

OK.

"In this BJ variant, using the example of a 2 card total of 20, I have the option of placing the ‘double up wager’ (equal to my original bet - pays 1/1). If however the dealer makes 20, I lose the double up wager and push the original.

Sounds too good to be true. He obviously won't make 20 more than about 40% of the time. So, you lose one unit 40% and win two units 60%. Why wouldn't you want to do that all day long?

"So for every situation of a 2 card 20 vs 10, I stand to win 2 units (original 1 unit, double up wager 1 unit) if dealer makes 19 or less or lose 1 unit if the dealer makes 20."

No, you also win the two units if he breaks his 10, no? That happens 23% of the time!

Don
 
#6
Yes, if he breaks his 10, I win both units also.
There is a little caveat which is if he draws to 16 at anytime, all bets push.
 
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#7
jacblacc911 said:
Yes, if he breaks his 10, I win both units also.
There is a little caveat which is if he draws to 16 at anytime, all bets push.
Just a wild guess here, but I would think that one caveat moves the needle to a house edge of about 1%? Anyone?
 

DSchles

Well-Known Member
#8
xengrifter said:
Just a wild guess here, but I would think that one caveat moves the needle to a house edge of about 1%? Anyone?
This needs to be simulated. A bit too involved to do analytically.

Don
 
#10
It’s ENHC - dealer takes all original bets if he gets BJ. So if you doubled 11 against Ace or split Aces vs Ace and dealer got BJ then you would lose all. BUT....If you split Aces vs Ace and get AT AT, then place the 'double up wager' on each and the dealer gets BJ, you just lose your original bets, not the doubled up wagers.
 
#11
DSchles said:
This needs to be simulated. A bit too involved to do analytically.
I am revising my estimate upwards, I have this pegged at 1.3% starting house edge, with a modified optimal BS.

Anyone else want to make an intuitive guestimate before wizard or someone else does a simulation assessment?
 
#13
xengrifter said:
I am revising my estimate upwards, I have this pegged at 1.3% starting house edge, with a modified optimal BS.

Anyone else want to make an intuitive guestimate before wizard or someone else does a simulation assessment?
The wizard has reported that he calculated a HE of 0.32%. That was based on a rule set of H17.
However what isn’t clear is whether or not the ENHC rule was included or not. If not, then can I just simply add the value of the ENHC disadvantage (-0.11) to this HE of 0.32% to get 0.43% HE?
Also, can I do the same with other values pertaining to different rule variations?
 
#18
This game exists in only one place in North America that I know of. I’ve tried to count at this game with mixed results. I determined it needs a specialized count and indices.
 
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