I don't know if all casinos allow this, but mine lets me add less than my bet when I double, or insure less than half my bet. Is this ever a good idea? Like, say, doubling-for-less a soft 15 against a three? Or insuring-for-less when the deck is only slightly positive?
Thx in advance.
trufaux
Doubling for less is almost never a good idea. When you double for anything, you give up your rights to take a fourth card. It is almost never worth it to do this if you can�t get the full money out there.
You can cook up some purely theoretical scenarios in which it could be optimal from a Risk Averse standpoint. But these examples are so far-fetched that they will not occur in ordinary BJ play.
Taking partial insurance is different. There are situation in borderline cases where optimal (i.e. Risk Averse) strategy is to take partial insurance.
I took even money on a blackjack, and didn't insure the other hand. 6 decks. TC was a little under 3. I thought of you when I did it. ;)
ETF
I like that play from a cover perspective. It would be even better if your other hand was something like a 16. Insuring a bad hand seems to a bit of a giveaway.
I once got a quick toss when taking insurance. The place was a bit of a low roller sweatshop and my 1-4 spread in green was sticking out like a sore thumb, so I was already getting some intense heat. I wasn't planning on coming back to the place in the future, so I said "screw it, I'm all-in" and shoved my remaining chips ($200) in the circle with a +6 TC.
Only problem was that the dealer turned an Ace-up and I was looking at a 9,7. I quickly flipped a $100 bill onto the insurance line. Sure enough - dealer has BJ. PC moved right behind me as the dealer flipped over the players cards. When she flipped over mine, the PC immediately gave me the tap. Most ploppies won't insure a 16 in the first place, but they damn sure won't do it after making a big deal of going "all-in" where they suddenly manage to locate another hundred.
> When you double for anything, you give up your rights to take a fourth card. It is almost never worth it to do this... <
Doubles frequently involve cases where you wouldn't take a 4th card anyway (e.g., 10 or 11 vs 4, 5 or 6), except in cases where the count was so extremely low you might not want to double in the first place.
To limit how much I will give back to the casino on a bad "streak," I use a "trailing stop loss" as part of my money management technique. I have on *rare* occasions "doubled for less" by throwing my last "available" cheques at a solid double down situation.
Please note that I said that �almost never worth it.� There are some very rare situations where it is optimal to double for less. Yes, they do come on doubles where a fourth card isn�t needed. (And possible against a 2 or 3 where a 4th card is unlikely)
However Money Management is NOT one of the reasons to do this, absent special circumstances like a tournament.
The reason one might do this is Risk Aversion. However, on these hands where you don�t need a fourth card, the doubling EV is huge. So the cirtical fraction is quite high.
Here is a slightly simplified analysis. As an example, let me look at A6 v 4. The EV for hitting is about 6%, the EV for doubling is about 12%. This is off the top of the deck.
This means that you optimally want about 6% of KEB in the betting square. If you had originally bet as much as 4% of KEB, you would want to add another 2% on your double.
However, there are rare situations where we would bet less than 3% of the top of the deck. In the other situations, you double for the full amount.
For other doubles, like 11 v 4, the EV is MUCH higher, making these fractions much higher.
> However Money Management is NOT one of the reasons to do this, absent special circumstances like a tournament. <
From a pure, theoretical, mathematical perspective, you are correct.
HOWEVER, the FACT is that this game is streaky.
I have found I make *much* more money using a trailing stop loss than I do by sitting there and toughing it out during a bad streak.
Call it voodoo if you want to, but it WORKS for me (and for at least one other who has posted on this board); so I'm going to stick with it.
