[Thranduil]

Deal: https://tinyurl.com/yqlaxjct

The double was takeout as per GIB's own system. Why by the nine hells does it pass then? Yes, it is unfortunate that it has a yarborough, but 4♠x, likely with an overtrick or two, is going to be a worse disaster than playing 5♦x. In fact, 5♦x goes down only two, which means it is a decent sacrifice here. One should only pass a takeout double if they are sure the doubled contract goes down, but never to show a weak hand.

Since cuebids of both 2♣ and 2♠ are "natural" in the GIB system in my position, I had no Michaels available and had to resort to the double to describe my hand - all I wanted was to know whhich of the two unbid suits it prefers.

[johnu]

As a general rule, offshape takeout doubles frequently end up in disaster, as GIB has no clue what's going on. I never make an offshape takeout double with GIB.

That being said, you've got a choice between overcalling 2♥ and making a heavy unusual 2NT.

As for GIB passing with a yarborough, I'm sure smerriman has a technical explanation about GIB logic.

[Thranduil]

johnu, on 2024-October-08, 05:20, said:

As a general rule, offshape takeout doubles frequently end up in disaster, as GIB has no clue what's going on. I never make an offshape takeout double with GIB.

That being said, you've got a choice between overcalling 2♥ and making a heavy unusual 2NT.

As for GIB passing with a yarborough, I'm sure smerriman has a technical explanation about GIB logic.

Thank you! I wouldn't really call that an off-shape takeout though. I have nothing in the bid suits, and want to play in either of the unbid suits. Does GIB play 2NT as showing hearts and diamonds in this position? I was considering 2♥. but thought that would undersell my hand and might cause us to miss a diamond fit. X on the other hand seemed to be the perfect bid for my hand considering the opponends bid both black suits.

[smerriman]

Thranduil, on 2024-October-08, 05:45, said:

Thank you! I wouldn't really call that an off-shape takeout though. I have nothing in the bid suits, and want to play in either of the unbid suits. Does GIB play 2NT as showing hearts and diamonds in this position? I was considering 2♥. but thought that would undersell my hand and might cause us to miss a diamond fit. X on the other hand seemed to be the perfect bid for my hand considering the opponends bid both black suits.

Double seems odd to me - opposite a human partner, I would assume it denies 5 hearts, otherwise there's far too great a danger of missing a 5-3 major fit. In fact, so much so, that if West had passed and I had 3-3 in the reds, I would respond in diamonds, since that's most likely to be our best fit (since you may well have doubled with 4-5 or even 4-6, but never the other way around).

But yes, 2NT would show a decent 5-5 here to GIB so that seems much better if you want to show both suits.

As for passing the second double, to be honest I'm not even sure what that double would show in a human partnership or when you're meant to pull it - it must have some willingness to defend, otherwise you would have continued with 4NT, wouldn't you? (Of course, GIB doesn't understand 4NT).

Despite the description, GIB doesn't really understand the double either, so can't even come up with options to simulate. But if I force it to simulate hands which match the description and then choose between P and 5♦, it still passes, because cases where you beat 4♠x, or let it make but were down 3 in 5♦ for a worse score, add up better overall.

Might need to put this one to polls to see how more advanced players than me interpret the doubles..

[thepossum]

Thranduil, on 2024-October-08, 03:51, said:

The double was takeout as per GIB's own system.

For what it's worth the official Gib card only has takeout up to 4 hearts

[Thranduil]

smerriman, on 2024-October-08, 18:07, said:

Double seems odd to me - opposite a human partner, I would assume it denies 5 hearts, otherwise there's far too great a danger of missing a 5-3 major fit. In fact, so much so, that if West had passed and I had 3-3 in the reds, I would respond in diamonds, since that's most likely to be our best fit (since you may well have doubled with 4-5 or even 4-6, but never the other way around).

But yes, 2NT would show a decent 5-5 here to GIB so that seems much better if you want to show both suits.

As for passing the second double, to be honest I'm not even sure what that double would show in a human partnership or when you're meant to pull it - it must have some willingness to defend, otherwise you would have continued with 4NT, wouldn't you? (Of course, GIB doesn't understand 4NT).

Despite the description, GIB doesn't really understand the double either, so can't even come up with options to simulate. But if I force it to simulate hands which match the description and then choose between P and 5♦, it still passes, because cases where you beat 4♠x, or let it make but were down 3 in 5♦ for a worse score, add up better overall.

Might need to put this one to polls to see how more advanced players than me interpret the doubles..

Thank you!

I can only go after the descriptions I see for the bids when playing with GIB. If an X is described as a takeout, I assume it is one - as in showing the un-bid suits and denying holdings in the opps' suit(s). If the description is incorrect, as it seems to be the case here, it should be changed. Is there a place to report issues like incorrect bid descriptions to BBO staff? With a human partner, I would have bid 4NT instead of the second X, of course. And either 2NT or 2♠ Michaels depending on the agreement in the first place.

The fact that both 2♣ and 2♠ are natural to GIB probably confused me so that I did not consider looking for what 2NT means to GIB and instead went for the X to show the two unbid suits.

[Thranduil]

https://tinyurl.com/yueln6g7

Here is an example where GIB gets it completely wrong with a double in the other way - and with just 2 measily points, it bids 3♥ - red vs green of course, and it goes down -800 against a part score. My hand was not off-shape and even quite a bit stronger than what I promised with 15HCP (passed in the first round to get the deal passed out, was in a robot race). No sane human would ever bid anything with N's hand over the opponent's 3♣.

[smerriman]

Thranduil, on 2024-October-09, 08:05, said:

I can only go after the descriptions I see for the bids when playing with GIB. If an X is described as a takeout, I assume it is one - as in showing the un-bid suits and denying holdings in the opps' suit(s). If the description is incorrect, as it seems to be the case here, it should be changed. Is there a place to report issues like incorrect bid descriptions to BBO staff? With a human partner, I would have bid 4NT instead of the second X, of course. And either 2NT or 2♠ Michaels depending on the agreement in the first place.

The fact that both 2♣ and 2♠ are natural to GIB probably confused me so that I did not consider looking for what 2NT means to GIB and instead went for the X to show the two unbid suits.

The second double definitely shows shortness in spades, support for the other two suits, and extra strength - it couldn't possibly mean anything else, so the description seems fine. (You could quibble over the difference between a takeout double and a transferable values double, but typically they're synonymous at high levels). But I added a poll on BridgeWinners, and so far it's completely unanimous for pass, so it looks like GIB got this one right, however it got there.

2♣ and 2♠ natural is expert standard, I believe.

3♥ is silly on the second hand, of course, but you can guarantee silly things will happen after a psych. 3♥ being doubled and passed out isn't even on GIB's radar; and if you give some of South's cards to the opponents, they wouldn't have bid this way in the first place.