Quick BS question about doubling soft A2 through A5

[Banjoclan]

Hi,

I posted here instead of the advanced math section because I'm sure this isn't advanced but it bugged me so much I literally lost sleep over it last night. BS says to double A2 and A3 vs a dealer 5 and 6 and to double A4 and A5 vs a dealer 4,5, and 6. However, I don't see why. When we have A2 we have 3 or 13 so a 4 gets us 17, 5 gets 18.....8 gets 21. All the other cards get us 16 or less so dealer has to bust for us to win. So 5 cards "improve" us to 17+ and the other 9 we hope for a bust. The same goes for A3 except there the cards that improve us are 3 through 7, still 5 cards to 9. The thing is A4 is the same, it's just 2 through 6 and A5 is Ace through 5. Why do we double on the dealer 4s with these hands. I would think that if doubling on these two hands against dealer 4 were profitable than it would be profitable doubling with A2 and A3.

Anyway, I appreciate any responses and I'm sure there's something simple that I'm missing.

[Banjoclan]

Ah, I see. That makes sense. Should've posted before bed time.

[Banjoclan]

Really sorry for posting this now that I see it's discussed thoroughly on the next page.

[HowMany]

I never question basic strategy. I trust the math guys. All I have to do is memorize; and that's easy.

[BigJer]

BS says to double A2 and A3 vs a dealer 5 and 6 and to double A4 and A5 vs a dealer 4,5, and 6. However, I don't see why. When we have A2 we have 3 or 13 so a 4 gets us 17, 5 gets 18.....8 gets 21.

Because a six - be it dealer or player - is such a bad card that you are better off DD against it.

Also, I have 2+ basic strategies memorized. One for H17 and S17. The EV isn't much but it makes me feel better. BTW if you can DD on any number of cards including after split then you don't start to DD until an A3 against a 6 then A4 vs 5,6 etc. BTW now I'm going to memorize BS for SP21. I will be the basic strategy master!

[njrich]

Ah, I see. That makes sense. Should've posted before bed time.

There are no stupid questions but there will be stupid answers(not referring to this site. Life in general).
Basic Strategy is the Foundation of every counting system and playing the game with any hope of deceasing the house edge.
Saying that Basic Strategy is wrong would be stupid but asking questions like you did to further understand it is Not.

[RS]

I had the same question a little while ago. Put simply, when you double down you give up the option to hit again, which is what you'd want to do if you draw and still have a soft 17 or less, as well as hard 12 or versus 2,3,or 4.

I don't like the idea of "don't learn how BS works just trust it". It seems a bit...ploppyish...to just memorize and trust.

[njrich]

There are some cases were the why is because it has the highest EV

That is the logic of it.
Memorizing the Charts is good.
Knowing why is better.

[RS]

Knowing WHY also helps if you're memorizing multiple tables. Why do you double Soft-19 in H17 but not S17? Understanding the WHY also helps memorize/remember when to jump in on someone's split or double down. Everything happens for a reason -- if there is no reason why we do something (mathematically / logically, not EV'y), we shouldn't be doing it, IMO.