[eyhung]

An interesting matchpoint partscore strain decision from the Blue Ribbon finals:

Scoring: MP

---

Partner opens 1♦ in 2nd, you respond 1♠, and partner rebids 1NT (12-14). Do you pass or do you sign off in 2♦ (via 2♣ two-way puppet checkback?) I thought one of the choices was obvious, but a friend I respect who was also in the finals thinks the other choice is obvious. So which of us is out of sync?

[peachy]

eyhung, on Dec 5 2009, 02:26 PM, said:

An interesting matchpoint partscore strain decision from the Blue Ribbon finals:

Scoring: MP

---

Partner opens 1♦ in 2nd, you respond 1♠, and partner rebids 1NT (12-14). Do you pass or do you sign off in 2♦ (via 2♣ two-way puppet checkback?) I thought one of the choices was obvious, but a friend I respect who was also in the finals thinks the other choice is obvious. So which of us is out of sync?

NT scores better at MPs. And this is the ultimate MPs... !

[cherdanno]

Easy pass, we may often have +120 on. With a weaker hand of the same shape it would make more sense to remove to 2♦.

[suokko]

Positive for 2♣ is that your hand is very suit oriented so I would think this could make 2 tricks more than NT. Downside in transferring to ♦ is that opponents balance to ♥ partial more easily and points might even be 20-20.

1NT at least rates to make because you hold combined 20-23 HCP.

Also your opening style affects decision because some never open 3 card ♦ and some open more often than just with 4-4-3-2 shape.

[kfay]

I had a hand like this in the club last Thursday....


I played in diamonds.

[655321]

I am in the 'definitely pass 1NT' camp.

1NT looks like a good contract. By passing now, the only way for opponents to get in is for LHO to find a bid when he could not do so on the previous round. If you puppet to 2♦, either opponent can make a takeout double of diamonds and get into the auction.

[kenrexford]

Some of this depends on the style of opening with minors. Onbiously, IMO, converting to 2♦ is right opposite an unbalanced approach, but that would obviously be mentioned.

If 1♣ is opened when 2344/3244, and if the opening style is not "better minor" (no chance of 3433), then Opener must have four diamonds. Further, he has five diamonds unless he is 2443 or 3442. Only in the 2443 situation do the opponents lack a parallel 8-card fit.

So, if the vulnerability were NV-NV, this would be a clear 2♣ call, IMO. You wouldn't be playing 1NT anyway, so get the strain settled now rather than later.

At these colors, though, with no interference yet, passing seems to be the matchpoint call.

That said, this is another reason to play an unbalanced diamond, IMO. If you are going to leave this at 1NT, then who cares what Opener's minor holding is? If he's unbalanced, I know what to do.

[Jlall]

Obv pass, it's MATCHPOINTS.

[eyhung]

suokko, on Dec 5 2009, 06:20 PM, said:

Also your opening style affects decision because some never open 3 card ♦ and some open more often than just with 4-4-3-2 shape.

3-card diamond holding by opener is irrelevant. Partner can't be 4432 because he would have raised spades. We do not open any other 3-card diamond suits.

[nigel_k]

I would prefer 2♦.

Probably I should run a simulation on this but my gut feeling is that diamonds will outscore NT on average. While it is easier for them to balance over 2♦, if they balance after I pass, it will be harder for partner to compete when that is right.

[wclass___]

Quote

Probably I should run a simulation on this but my gut feeling is that diamonds will outscore NT on average.

Not a gut feeling, but some logical assumptions.
This hand has a catastrofal lack of spot cards (very important for NT), ruffing values, aces, support.
For NT to be better you need 8NT tricks (unless you think that 1N makes and 2♦ goes down) and hope that diamonds doun't play 2 tricks better.
I belive that extra ♦ tricks(and 1N-1, 2♦=) are more probable than 2N= and 2♦+1
Pass feels like a dogmatical view, however i might be convinced otherwise with sim proving that.

[hanp]

I did a double dummy simulation.

I gave partner 12-14 HCP, 2-3 spades, 2-4 hearts, 4-5 diamonds and 2-4 clubs. I precluded partner from having 3 spades and 2 hearts headed by the jack or lower. I also did not allow for 2254 shape.

I gave LHO at most 11 points, no 6+ cards in spades, hearts or diamonds, and no 7 clubs. I also took out all hands where LHO had 9-11 HCP and 4+ hearts and clubs.

I rejected all hands where RHO had a 6-card major or a 7-card club suit, and I restricted RHO from having a 5-card major and 9+ points.

This is still quite far from realistic. Most importantly, I forgot to remove RHO's takeout doubles.

Results: out of 500 hands at matchpoints, 2D beats 1NT 286 times and loses 129 times. It draws 191 times. For data lovers: 2D scored 8.66 tricks on average and 1NT scored 7.03 tricks on average. 2D made 91% of the time and 1NT 69% of the time.

Quite an overwhelming (double dummy) victory for 2D. The simulation does show that the optimal lead is quite a bit more restrictive against 1NT than against 2D, perhaps suggesting that in real life it is harder to defend against 1NT.

[eyhung]

hanp, on Dec 7 2009, 04:33 AM, said:

Quite an overwhelming (double dummy) victory for 2D. The simulation does show that the optimal lead is quite a bit more restrictive against 1NT than against 2D, perhaps suggesting that in real life it is harder to defend against 1NT.

I'm glad someone had time to do a sim -- I'm still in San Diego (airport). I was going to run one myself when I got home. I think 2♦ is the clearcut contract here with the lack of spots, aces on the side, the ruffing value, and the jack of trumps, and I bid appropriately. But apparently popular opinion is against me.

On the actual partner hand opposite, diamonds was three tricks better than NT double-dummy when partner flopped 5 diamonds to the QT, so on this one hand, my judgement was vindicated. 2♦ +110 was worth 21.5 out of 37, beating 1NT (which is down 1 double-dummy).

FWIW, my LHO did think about bidding 2♥ in the balancing seat, but had he done so, he would have regretted it -- partner had KQJT of hearts and he would be going for a huge number.

The score distribution on the actual hand :

1400 1 [2H doubled?]
1100 1
800 1
400 1 [2H undoubled, probably, since we are vulnerable]
200 1
200 1
150 1 [3D making 5 or 1NT making 3, can't tell]
120 3 [1NT making 2]
110 14 [2D making 3]
90 6 [1NT making 1 -- diamonds are ice-cold for 9 tricks in an expert field]
-90 1
-100 7 [1NT down 1]
-200 1 [1NT down 2? 5D down 2?]

[kenrexford]

It's tough to assess a bidding problem from the standpoint of actual results, as this was obviously one case out of many.

The two keys to this hand that seem critical are (1) the difficulty of defending 1NT single dummy and (2) the likelihood of various holdings that might have been, and well as a possible (3) the various auctions after a pass and after a 2♣ call as alternatives.

On that third note, I wonder how many 1NT contracts ended up pushed to 2♦, and how often other calls at some other point may have affected defense.

[Phil]

Late here, but 2♦ was my first reaction.

If I'm not bidding it, its because I'm worried about a heart balance, not because I think we are scoring better.

HanP's sim is more valuable to me if we can build in the expected number of tricks in hearts if the opponents balance.

[kfay]

655321, on Dec 5 2009, 08:53 PM, said:

By passing now, the only way for opponents to get in is for LHO to find a bid when he could not do so on the previous round. If you puppet to 2♦, either opponent can make a takeout double of diamonds and get into the auction.

I agree with this in principle and I've had a few people mention this point to me before.

However, to me it seems like the same argument as 'don't push the opponents to a game unless you're sure you can beat them.' Good opponents will bid the game, and good opponents will balance us out of 1NT when it's right.

Not really arguing against you since I agree with the standpoint, in principle, but it does seem that way to me so I can't take it as dogma.

[aguahombre]

If I take NT out to 2D (directly or through convolution), partner will know how many diamonds we have in addition to our combined strength. that can't be all bad.

[jonottawa]

I voted pass. I think it's close.

[jdeegan]

Ellllllllllllll Pasooooooooooooooo
It is MP, and you have the clear balance of HCP strength. Signing off in 2♦ is a clear shot in this field. Not crazy if you need a board, but way against percentages.

[Jlall]

kfay, on Dec 7 2009, 01:05 PM, said:

655321, on Dec 5 2009, 08:53 PM, said:

By passing now, the only way for opponents to get in is for LHO to find a bid when he could not do so on the previous round.  If you puppet to 2♦, either opponent can make a takeout double of diamonds and get into the auction.

I agree with this in principle and I've had a few people mention this point to me before.

However, to me it seems like the same argument as 'don't push the opponents to a game unless you're sure you can beat them.' Good opponents will bid the game, and good opponents will balance us out of 1NT when it's right.

Not really arguing against you since I agree with the standpoint, in principle, but it does seem that way to me so I can't take it as dogma.

What? It's much more dangerous to balance when they're in 1N than when they're in 2D. Presumably if they're in 2D they have a fit, that makes bidding quite safe since you (almost always) also have a fit. If they're in 1N they often have no fit so it's much tougher to just bid something.

I would consider it pretty widely accepted that people balance/compete on fit auctions and pass on misfit auctions in general.