[uva72uva72]

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IMPS, ACBL robot individual

I earned my 10-IMP loss here because I failed to follow my own rule of ALWAYS checking the notes before making a bid. Still, I had a lot of company in missing this game. Presumably my fellow underbidders were also unaware that the robots play negative free bids in this sequence.

[steve2005]

uva72uva72, on 2015-September-26, 12:24, said:

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Presumably my fellow underbidders were also unaware that the robots play negative free bids in this sequence.

2♥ is not a negative free bid. A negative free bid has an upper limit usually most can have is 10-12, some even play lighter and varies by partnership. Your bid is described as unlimited.

[1eyedjack]

I think that part and parcel of negative free bids is that double followed by new suit is stronger than NFB and is forcing. I also think that the bottom of the range to bid a direct 2H would be weaker than that described here. I do not believe that GIB plays that way, and from recollection I think that new suit via X would show a weaker hand than direct 2H as described.

I don't think that you should read too much into the fact that "your bid is described as unlimited". It may have been described as unlimited but it appears to have been interpreted as limited. Where there is a mismatch between interpretation and explanation, why would you put faith in either (in this case explanation) at the expense of the other? If anything, forced to choose, then except in the case of "obvious bug" I would assume MI.

There is another possibility: GIB may have included a powerhouse as a possibility for South and yet after doing some sims decided that on grounds of frequency you are more likely to overreach opposite a minimum 2H than to miss game opposite a 2H that happens to have extras. Not a healthy piece of code, I think, if that is the explanation.

[Bbradley62]

I still think there needs to be a global change to say that every bid that is described as unlimited is forcing one round. If it's not really unlimited, then fix the provided explanation.

[iandayre]

About a year ago I had GIB perpetrate a similar auction with me, passing a forcing new suit bid by an unpassed hand. In my post, I pointed out that nowhere in the system notes are negative free bids shown, therefore I have every right to assume that a new suit is forcing. My recollection is that someone from BBO agreed, and that in a subsequent release such bids were established as forcing. And I must say, I have not had GIB pass one since that time. Clearly it did so here, and it would seem that the fix must be re-fixed.

I am quite sure that Jack is correct, in GIB's methods a negative double followed by a suit bid is limited and non-forcing. So also allowing GIB to pass a new suit bid by an unpassed hand is unplayable.