[Thranduil]

Hand link: https://tinyurl.com/24p2ucp5

Why does the robot think it has to show 9xxx in ♥ when we already have a ♦ fit? And why does it insist on its garbage hearts when I deny support (again, because I already said I have not more than three hearts with the 2NT)?

[smerriman]

Are you sure you want to know..

The most important part is that GIB plays 2NT as showing a strong hand, and even more so when vulnerable - 15+ points - not a weak hand. Yes, 15+, not 12+ like the description says (though you weren't even close to that). If North had passed your partner would have responded 3♠ to force to at minimum 5♦; all of this is massively broken and discussed in this thread.

But if this wasn't broken enough, doubles always break GIB even more, since most of the sequences are defined in the database only when the opponents pass:

- after North's first double, 3♠ and most other bids are now undefined, and the only option it has is the same way it would bid with 0 points, even though it think it's strong enough to force to game
- after North's second double it gets a second shot at forcing to game, with its rules about constructively looking for a 4-4 major game after a minor raise having higher priority than passing the double for some reason
- after 4♦, it's still in a game force situation, but it's not allowed to bid 5♦ itself because there is a rule that says if partner passed you in a suit at a lower level, you can't raise them in that suit later..

[johnu]

Good bidding by GIB. I aspire to bid that well some day.

[pescetom]

I think the bottom line is that this is one of the many conventions to simply avoid using with GiB because it is incapable of follow ups, just like almost all of (the already dreadful) Cappelletti.