[iandayre]

I just held this remarkable hand on the last board of an ACBL Robot IMP Tournament:

AKQJxxx
Kxxxx
A
Void

And the auction went 1C on my left, 1H by my partner and 2C on my right. Given that GIB does not play Exclusion, and I would have undoubtedly been left to play there had I bid 5C, I saw little alternative to 4NT. Partner had an Ace, I bid the grand, and naturally partner held the Ace of Clubs.

Oh well. I know Exclusion doesn't come up that often, but it doesn't seem like a difficult convention to program for limited use. It should also be used after Texas Transfers.

[manudude03]

5NT grand slam force? It won't get you there opposite Axxxx, but it will ensure you get to it opposite AQxxx while staying opposite QJxxx.

[1eyedjack]

manudude03, on 2016-October-24, 16:45, said:

5NT grand slam force? It won't get you there opposite Axxxx, but it will ensure you get to it opposite AQxxx while staying opposite QJxxx.

My expectation is GIB would put you in 7N.

[lycier]

1eyedjack, on 2016-October-24, 20:14, said:

My expectation is GIB would put you in 7N.

Really?
Now let me edit a similar hand to show what would happen.

Hand-1

---

Hand-2

---

Hand-3

---

So I am gonna have to say Gibs are doing a very good job !!!

[iandayre]

manudude03, on 2016-October-24, 16:45, said:

5NT grand slam force? It won't get you there opposite Axxxx, but it will ensure you get to it opposite AQxxx while staying opposite QJxxx.

Yes you stay out with the actual hand, but miss the good/cold grand with Axxxx or better. Seems like that is more likely than partner having the wrong Ace, but I don't know how to compute the odds.

[jdonn]

Sorry I know for sure exclusion blackwood is harder than you think. And the time spent is way more valuable if used on regular blackwood, which has plenty of problems of its own. Or on a million other things.

[johnu]

Kickback grand slam force would let you find ace (fifth) in hearts so you could get to a 78++% grand but GIB doesn't play any kickback conventions. I would have bid a pedestrian 5NT grand slam force.

[iandayre]

johnu, on 2016-October-27, 02:43, said:

Kickback grand slam force would let you find ace (fifth) in hearts so you could get to a 78++% grand but GIB doesn't play any kickback conventions. I would have bid a pedestrian 5NT grand slam force.

Not saying that is wrong, just wonder if that is better than what I did. With partner overcalling H and both opponents bidding C, seems like if partner has one Ace it is odds on to be H.

Thank you for your comment Jdonn, I accept it. To me, biggest BW problem is that GIB can make the 5NT King ask, but doesn't know how to use this information. There have been several hands where GIB could easily count 13 tricks after a side king is shown, but still signs off at 6. In fact, at one time I posted that I have never seen GIB bid a grand after using 5NT. Asked for examples from others and got nothing.

[johnu]

iandayre, on 2016-October-27, 11:35, said:

Not saying that is wrong, just wonder if that is better than what I did. With partner overcalling H and both opponents bidding C, seems like if partner has one Ace it is odds on to be H.een GIB bid a grand after using 5NT. Asked for examples from others and got nothing.

When you guess wrong about which ace is present, you lose a slam swing and the maximum number of IMPs. In a very mixed field like ACBL robot games, a large percentage of the field will usually not get to a grand slam no matter how cold it is (4♠ anyone ). If partner doesn't have ♣A, it's pretty likely that they have ♥AQ.

If you behind going into 12, and want to do some gambling to finish 1st and you don't care about dropping a lot of places, then Blackwood is the way to go. If you are grinding, then GSF won't get you to some grands, but won't give you a huge minus score.