Double for less

[vneck]

Twice in the past few sessions I've seen 2 different players double for less... even though they had the chips for a full double. Is there some sort of math (maybe at fractional true counts?) that makes this a correct move?

 

[gronbog]

Double for less is only correct basic strategy when you can't hit or in games with re-doubling allowed. In a regular game, it is never correct basic strategy or correct index strategy to double for less, but people do it because they are afraid to double for the full amount. It is possible to turn a +EV hand into a -EV hand by not doubling for enough.

Edit: The statement in bold is incorrect. See my correction below.

This can be an opportunity for you. It is a +EV move to offer to top up their double. Just make sure you make it clear that you are to receive your bet back plus the winnings if the bet wins.

 

[vneck]

Great advice. Never knew that "top off" option existed. Everytime I think I'm starting to gain some knowledge about this game I realize how much I don't know. Very grateful to this community.

 

[gronbog]

It is possible to turn a +EV hand into a -EV hand by not doubling for enough.

Thanks to Don S for pointing out to me privately that this is not true. What I meant to say is that, by doubling for less, your EV may become worse than that of hitting.

 

[gronbog]

Great advice. Never knew that "top off" option existed. Everytime I think I'm starting to gain some knowledge about this game I realize how much I don't know. Very grateful to this community.

Not all casinos nor all players will allow you to do this. Misunderstandings about what happens when the bet wins or loses along with outright reneging on the "agreement" can be problematic. Once again make things very clear with the other player. Make it seem like you are "helping" them to make the correct play.

Another note. A similar play is putting up the entire amount of their double when they want to hit. In this situation, by placing the entire double amount, you are hurting the other player by limiting them to one card, where they could re-draw as needed if they hit. In the previous situation, you're not hurting the other player because they have already committed to taking one card by wanting to double for less. Some players may find putting up the entire double amount unethical.

 

[vneck]

These scenarios are very interesting. I'll post if I get a chance to try this in a future similar situation