Hmm

[kenberg]

The robots use the auction 1NT-3M to show a singleton. Often (although maybe the robots don't require this) the 3M call also stipulates that the other major will be a three card suit.

Now the robots also play minor suit stayman. So I started thinking about this.

AJ2
8
J986
K9875

Partner opens 1NT.
I can bid 3H. I can also bid 2S. I gave it to the robots. They went with 2S.

1NT-2S-3D-3H(this also shows a stiff, or void)-5D. Making 5. NT is hopeless.

I have to think about this. I am inclined to think that when responder is 3-1-4-5 with game forcing values opposite a NT opening, the auction is apt to start 1NT-2S rather than 1NT-3H. That's what happened with the hand I gave them, Perhaps I will experiment around a little more.

I have played the 1NT-3M(3M=stiff) agreement with some people, including the robots, but I can't recall 1NT-3M  ever coming up. Maybe I can now see why.

Any thoughts?

[wackojack]

Here is a "back-of-envelope" estimation of your chance of getting this bid in:
Chance of partner having 15-17 points = 10.1%
Chance of partner having an opening 1NT distribution = 40% approx.
Then the chance of partner opening 1NT = 4%
Chance of getting any strength M31m54 distribution = 2%
Chance of getting a game force hand opposite 1NT = 50% approx.
Then chance of getting a M31m54 game force opposite 1NT = 1% approx.
This will be reduced according to how freely opponents intervene or open ahead of you  Say 20% of the time.
Then chance of getting an unopposed game forcing M31m54 = 0.008 * 0.04  =  3.2 * 10-4  i.e. approx 3 in 10,000. 

So the reason it does not come up is not that mss if used takes away some of the opportunities.
I have found it to come up a couple of times but both were when partner wasn't playing this convention.
 
Another distribution that has come up a few times has been 5-5m where you can play 1N-2N (transfer)  and pass partner's rebid if you play step 1 as dislike and step 2 as like.  And 1N-3D as game force 5-5m and sadly partner did not play the convention.

[kenberg]

Yes, both mathematically and on experience it does not appear often. I was just having some fun seeing how it goes. I tried the same responder hand again with opener having 4=3=3=3, with strength in the spade holding/

The auction went 1NT-2 -2NT-3 - 4 making. It's not totally trivial to see how to get to 4 without some gadget. So it can be useful when the blue moon is out and the hand makes its appearance.

But again it is mss that came to our rescue.

Ah ha. I just looked and the robots, for 1NT-3M, to requires 4 cards in each of the other suits, if the jump is on a stiff, and if the jump is on a void then the other major has four cards and the minors or 5/4.

Yep, not every day.

[jcreech]

The treatment I am most familiar with did not employ MSS in addition to the 3-level bids.  With four in a major, we always started with Stayman, and the 3-level major was a fragment with 4-5 in the minors.  The goal was either 3NT with the unbid major covered, or a minor-suit contract if not.  We bid the fragment because it was harder to make a lead-directing double, when it could be passed on a 4-3 fit below game.

It was also a bid that seemed to be more frequently bid than Ken has noted for the "splinter,"  though now we have a better understanding of how rigid the requirements actually were.  I am certain that the frequency was also improved by the absence of MSS.

[wackojack]

Don't forget that you can use 1N-3 to find a 5-3 major suit fit.
Below is I think a good schedule of responses to cater for all hand types opposite 1N. I hope there are no typo's

Summary of responses to 1NT i
Weak hands

5+♥/♠       Transfer 2♦/♥
5♠+4♥      2♣ Stayman and over 2♦ bid 2♠ 
4♠+5♥      2♣ Stayman and over 2♦ bid 2♥
6+♣/♦           Transfer 2♠/NT or pass with no singleton
4351 or 4450   2♣ Stayman and pass re-bid
55m      2NT and pass 3♣ or 3♦ re-bid
Other balanced   Pass

Invitational hands

5♥/♠      Transfer 2♦/♥    Then 2NT
5♠+4♥      2♣ Stayman and over 2♦ bid 2♠ forcing to 2NT
4♠+5♥      Transfer 2♦ to 2♥ then bid 2♠           
6+♣/♦           Transfer bid 2♠ with 6+♣ (The 1NT opener rebids 3♣ with ♣Qxx or better)
      Transfer bid 2NT with 6+♦ (The 1NT opener rebids 3♦ with ♦Qxx or better)
43M51 or 44M50   2♣ Stayman and raise if 4-4M otherwise pass re-bid
55m      2NT and pass 3♣ or 3♦ re-bid
6♥      2♦>2♥>3♥
6♠      2♥>2♠>3♠
Other balanced   Pass


Game forcing  hands

5♥ 332      Transfer 2♦, then 3NT over 2♥.  Opener then judges final spot
5♠ 332      Transfer 2♥, then 3NT over 2♠.  Opener then judges final spot
5♥ 4♠      2♣ Stayman, then over 2♦ bid 3♠. (Smolen)
4♥ 5♠      2♣ Stayman, then over 2♦ bid 3♥. (Smolen)
55M      Transfer 2♥, then over 2♠ bid 3♥
55m      3♦ = 55+ m. 
5♥ + 4m      2♦-2♥-3m      
5♠ + 4m      2♥ -2♠-3m   
4♥ + 5m      2♣ Stayman, then over 2♦ or 2♠ bid 3m   
4♠ + 5m      2♣ Stayman, then over 2♦ or 2♥ bid 3m   
3♠+1♥ +54m   3♥ splinter,
3♥+1♠ +54m   3♠ splinter
4M +6m      2♣ Stayman, then if partner does not hit your 4M bid 3m
6♣ 331       2♠> (2N or 3♣) > 3♦♥♠ = singleton
6♦ 331.      2NT>(3♣ or 3♦) > 3♥♠ = singleton
3M+ 2OM   3♣ 5 card Stayman
6+♥ no slam interest    4♦ Texas
6+♠ no slam interest    4♥ Texas
6+♥ slam interest      2♦>2♥>4♥
6+♠ slam interest      2♥>2♠>4♠

[kenberg]

Jack, that is very useful. When I play online, I usually just hope nothing complicated comes up in the bidding and hope I can do well in the play of the hand. I think it was Eric Dodwell who said something like "I don't know whether bidding or play is more important but I would like it to be the play". But now that Pat and I have agreed to play in this upcoming tourney it would be a good idea for the two of us to get things straight. I suggested, and Pat happily agreed, using the same system the robots use, see https://www.bridgebase.com/v3/, so now I have to read it carefully. Back in the old days I would get a pard, we would agree to play as written somewhere that both thought reasonable, and that was that. Playing remotely gets more complicated or at least it can.

The bots use 1NT -2S as minor suit stayman so they use 1NT-2NT as a trf to clubs and 1NT-3C as a transfer to diamonds. Everything comes with a cost, this agreement prevents 1NT-3C as being Puppet. Pat and I have agreed that we can overrule  Gib but the default is to play things the Gib way. Since bad bidding results are often caused by confusion rather than by system, I'm fine with leaving it be.

Anyway I hope that both we and our opponents avoid the sort of swings where a pair plays in a 3-1 fit because one person thought their bid showed a stiff and the other thought it showed a five card suit. your list of agreements can be a good starting point for us and for others.