[blindsey]

What should a double of the Serious 3NT bid mean? Assume the doubling side has not previously bid.

[smerriman]

I misclicked?

[Tramticket]

Modern bidding boxes still include the dark blue Redouble cards.

Whatever meaning you want to attribute needs to be based on a hand which can cope when 3NT comes back to you redoubled. Maybe you have a suit that is playable at the four-level? Strange that you didn't choose to bid it earlier in the auction. Maybe you are confident that you are defeating 3NT, because you will be on lead with AKQJ10 in a suit?

If these seem unlikely, you might choose not to double a Serious 3NT slam try.

[Cyberyeti]

Tramticket, on 2023-October-13, 01:44, said:

Modern bidding boxes still include the dark blue Redouble cards.

Whatever meaning you want to attribute needs to be based on a hand which can cope when 3NT comes back to you redoubled. Maybe you have a suit that is playable at the four-level? Strange that you didn't choose to bid it earlier in the auction. Maybe you are confident that you are defeating 3NT, because you will be on lead with AKQJ10 in a suit?

If these seem unlikely, you might choose not to double a Serious 3NT slam try.

This is fair, the only time I'd consider it might be possible is if you originally would have been bidding over a short club, have a huge number of clubs and aren't sure when club bids are natural. In this circumstance I might consider it as "lead a club, I have lots of them" and am prepared to bail there if necessary.

Would you ever double a frivolous 3N ?

The biggest danger might be that if you give this a specific meaning, it allows opps to choose correctly whether to bid a slam and which one rather than a redouble.

[sfi]

Aside from giving them the chance to play 3NTxx, doubling also gives them extra useful space when looking for slam. Any meaning you assign would have to be valuable to your side and hard to show later in the auction. If it's a specific lead, they'll often reveal that while cuebidding anyway, or your side may be able to double something for the lead.

You may be able to find a good meaning for it, but IMO smerriman covered it well in the first response.

[DavidKok]

The extra bidding space alone often makes doubling on slamgoing auctions a net loser. Even a system as rudimentary as "pass = I do not know where we are going, XX = I like playing 3NTXX, bidding = a more enthusiastic control bid than it would have been without the double" is more than likely sufficient compensation for any information you have shared with your partner through the double.

[blindsey]

OK, I guess there was a reason I couldn't think of a good meaning for this bid. Apparently there isn't one.

[Gilithin]

blindsey, on 2023-October-13, 07:13, said:

OK, I guess there was a reason I couldn't think of a good meaning for this bid. Apparently there isn't one.

I can only think of 2. One would be lead-directing for a specific suit and the other would be a very shapely 2-suiter.