[pickabidp]

Can you open 1NT with a singleton?
Would you have to alert or add to announcement.
As in 11-13 may be unbalanced.
Can not seem to find a definitive answer in the
ACBL Convention Chart.
Under definitions:
1. 'A no trump opening or overcall is natural if
not unbalanced (generally, no singleton or void and only one or two doubletons).

I did not find an ACBL Laws forum, not sure this is right spot to ask question.

[hrothgar]

pickabidp, on 2015-March-04, 15:47, said:

Can you open 1NT with a singleton?
Would you have to alert or add to announcement.
As in 11-13 may be unbalanced.
Can not seem to find a definitive answer in the
ACBL Convention Chart.
Under definitions:
1. 'A no trump opening or overcall is natural if
not unbalanced (generally, no singleton or void and only one or two doubletons).

I did not find an ACBL Laws forum, not sure this is right spot to ask question.

In the ACBL, you can not have an agreement to open a natural one NT with a singleton, however, you may open a natural 1NT with a singleton.

[blackshoe]

You cannot agree to open a natural 1NT with a singleton. You are allowed to deviate from your agreements, so long as you don't do so frequently enough to establish new agreements.

You cannot legally embellish announcements. The alert procedure defines what you say.

[pickabidp]

Please..not to question the answers so far..
but I can actually find nothing that says you can not..??
found this :

http://www.bridgebas...nt-opening-bid/
Not sure which answers were actually agreed on. I could not get the link to Mike Flader article to work.

Is 'generally' a limiting factor? Is this than
some percentage. So if you did open 1NT less than (lets say ) 5% with a singleton (any singleton)would that still be 'generally'.
There is no 'agreement' on how responder can 'ask' if you have a singleton. There is no
agreement that you always have to open a 11-13 hand with a singleton 1NT.
Not trying to disagree but I just can not find anything in the Alerts or Convention charts that
specifically says you may not.

[hrothgar]

pickabidp, on 2015-March-04, 18:19, said:

Please..not to question the answers so far..
but I can actually find nothing that says you can not..??
found this :

http://www.bridgebas...nt-opening-bid/
Not sure which answers were actually agreed on. I could not get the link to Mike Flader article to work.

Is 'generally' a limiting factor? Is this than
some percentage. So if you did open 1NT less than (lets say ) 5% with a singleton (any singleton)would that still be 'generally'.
There is no 'agreement' on how responder can 'ask' if you have a singleton. There is no
agreement that you always have to open a 11-13 hand with a singleton 1NT.
Not trying to disagree but I just can not find anything in the Alerts or Convention charts that
specifically says you may not.

Comment 1: The GCC is constructed such that any (non natural) bid that is not explicitly sanctioned is forbidden.

Comment 2: Don't try to make sense of Mike Flader's blathering

[blackshoe]

Try this article.

[pickabidp]

blackshoe, on 2015-March-04, 20:33, said:

Try this article.

Thanks for the link to that article.

The use of terms- ( in that article)
" no more 1% of the time"(assume that means)
(no more 'than' 1%)
"sound bridge judgment "
"When a NT opening hand contains a singleton or void, the Director needs to look into the overall system to determine whether an infraction has occurred."
Re system:
We play Precision (form of) with a weak NT opener in 1st or 2nd seat.
Openings (1d,1h,1s,2c,2d) are 11-15.
We would like to try to make the 1H/S opening show either 14-16 or distributional hand (5-5)
To do that we need to be able to open 1NT with a 5 card major. The problem hand, 1345.

Hands with singletons: 5431 type

1-5-4-3 1-5-3-4 1-3-5-4 1-3-4-5 1-4-5-3 1-4-3-5
3-5-4-1 3-5-1-4 3-4-5-1 3-4-1-5 3-1-4-5 3-1-5-4
4-5-1-3 4-5-3-1 4-3-5-1 4-3-1-5 4-1-5-3 4-1-3-5
5-4-3-1 5-4-1-3 5-3-1-4 5-3-4-1 5-1-3-4 5-1-4-3
= 24
Exceptions:

1-3-4-5 1-3-5-4 3-1-5-4 3-1-4-5 open 1D (4)
4-5-1-3 4-5-3-1 open 1H (2)
5-4-3-1 5-4-1-3 open 1S (2)
1-4-3-5 3-4-1-5 4-3-1-5 4-1-3-5 open 2C (4)
= 12
Hands with 5K Majors:

5-4-3-1 5-4-1-3 5-3-1-4 5-3-4-1 5-1-3-4 5-1-4-3
1-5-4-3 1-5-3-4 3-5-4-1 3-5-1-4 4-5-1-3 4-5-3-1
= 12

This leaves us with 12 hands that we would open 1NT on with singleton.
(maybe opening all hands with a 5 card
spade suit 1S might be an addition to
exceptions)
percentages:
Distribution 5431 12.93% of time
HCP

You get 11-13 points 23.88% of time
you would get 11-13 in 1st 12%
5431 ( 13% of 12%) = 1.56 %
Help??
No idea if this math works..
but it seems that you would open 1NT with a
singleton 'rarely.
And if it is part of a system, does it qualify as
'sound bridge judgement'?
Is there a place to present this, probably in a
better format, to see if it would be allowable.
Partner 'does assume' the 1NT is balanced and
'maybe' in a slam seeking auction Responder 'might' be able to deduce a singleton.
Any further input appreciated, TIA

[barmar]

You're not likely to get a precise definition of this, since it's all about judgement calls. It's similar to trying to determine whether a pair has an implicit agreement when they make some similar psychic calls. Even the definition of "psychic" is vague (there's no precise definition of a "gross deviation") and may even require mind reading (it has to be "intentional", otherwise it's just a misbid).

[hrothgar]

pickabidp, on 2015-March-06, 14:13, said:

Any further input appreciated, TIA

Once you go to the work to quantify this, it becomes an agreement and therefore verboten.

[BillHiggin]

pickabidp, on 2015-March-06, 14:13, said:

This leaves us with 12 hands that we would open 1NT on with singleton.
(maybe opening all hands with a 5 card
spade suit 1S might be an addition to
exceptions)
percentages:
Distribution 5431 12.93% of time
HCP

There is a certain risk involved with quoting only part of a post as I have done here! But, this paragraph seems to go to the heart of the matter. The OP actually IS designing a system which requires opening 1N on certain hand patterns which include singletons. At this point, all discussion of percentages is mute - the system runs afoul of (quoting from blackshoe's referenced article:

Quote

What IS prohibited is any agreement that such bids do not promise balanced hands.

Once you agree to do it, how often you do it no longer matters!

There is a very real possibility that my reading/comprehension skills are faulty - if so, please accept my apologies.

[pickabidp]

Agree. But we all know very advanced players who would acknowledge that their partner (will-might-sometimes)open 1nt with a singleton.
Advance agreement?
So does this then override:
"There is not now, nor has there ever been, any regulation which prohibits a player from opening (or overcalling) a natural NT with a singleton if sound bridge judgment dictates doing so."

Or? A system in which unbalanced NT is part of.

Supposing -"sound bridge judgement" decides that
opening with the singleton is :

Players may use their bridge judgment to open or overcall a notrump with a singleton provided that: It is a rare occurrence (no more 1% of the time, partner expects you to have at least two cards in each suit, and there are no agreements which enable the partners to discover a singleton.)
OR
From ACBL convention chart:
A no trump opening or overcall is natural if
not unbalanced (generally, no singleton or void and only one or two doubletons).

Once again 'generally'..
So can you propose a 'system' to ACBL (or directors) and have it deemed 'sound bridge judgment"?

[hrothgar]

pickabidp, on 2015-March-06, 16:04, said:

So can you propose a 'system' to ACBL (or directors) and have it deemed 'sound bridge judgment"?

No

If you formalize this, it becomes an agreement
If it is an agreement it is not legal

[campboy]

The issue is: does your system require opening 1NT on a hand with this range and shape, or do you have an alternative systemic bid available which you decided not to use because of judgement? If you want to treat a 4441 as balanced because the singleton is a high honour and the suit you would otherwise have to open is weak, that's ok. If you have to treat it as balanced because there is no other way to bid it, that is not.

[mycroft]

I believe this is in the article, too, but paraphrasing:

• If there are hands with a singleton where the only possible call is 1NT, your 1NT call is considered "not natural" and also "not allowed" (on the GCC; Mid-Chart you're good provided it's minimum 15). Also,
  
• If there is any call in your 1NT structure that either asks for a singleton (in opener's hand) or shows a singleton (in opener's hand), you are deemed to have an agreement to open 1NT with a singleton (which is "not natural" and also "not allowed"). Either that, or it's a psychic control ("ANY partnership agreement which, if used in conjunction with a psychic call, makes allowance for that psych") - expressly DISALLOWED, because what a psychic control almost always is is "we're playing this system, which would be illegal if we said we were playing it, so we'll just 'psych it' when we have to and get out this way".

In the EBU and other jurisdictions you have a lot more freedom.

[Vampyr]

mycroft, on 2015-March-09, 11:56, said:

In the EBU and other jurisdictions you have a lot more freedom.

Yes, in the EBU you just have to include "may contain a singleton" in your range announcement.

To the OP: I am pretty aure that the 1% in the linked article is intended as 1% of your 1NT openers, not 1% of all hands.

[pickabidp]

Thanks to all the responders..
mostly because no one has asked
why would you want to open with a singleton.
System design goes like this:
For 1st/2nd opening..for team game..not pairs.
1C..Prec 16 UNB/17BAL
1D..11-15 may be short
1H..or..1S... 11-16
1NT 11-13
2C..11-15 5C if 4H/S or 6+C
2D..11-15 4441 or 5440
But <> We really want to have the 1H/1S show 14-16
That is the reason to open 1NT with the singleton!!!

To get to be able to open 1H/S 14-16
we have to get rid of the 11-13 hands..
extreme distribution is not problem or 4333 type
5431 is problem..

24 possible:

Scenario 1:
hands with 54 in minors want to open 1D.
1-3-4-5 1-3-5-4 3-1-5-4 3-1-4-5 open 1D (4)

With 5C and 4Maj..11-15
1-4-3-5 3-4-1-5 4-3-1-5 4-1-3-5 open 2C (4)

Leaves 16 hands with singleton that we would open 1NT.

Scenario 2:
Add hands that have 4S-5H Or 5S-4H
4-5-1-3 4-5-3-1 open 1H (2)
5-4-3-1 5-4-1-3 open 1S (2)

Leaving 12 to open 1NT..

Scenario 3:
Open all that have 5 S..1S
6 have 5 Spades..2 are already included so (4)
5-4-3-1 5-4-1-3 5-3-1-4 5-3-4-1 5-1-3-4 5-1-4-3

So that leaves 8 hands with a singleton to open 1NT with

1-5-4-3 1-4-5-3
1-5-3-4 3-4-5-1
3-5-4-1 4-1-5-3
3-5-1-4 4-3-5-1

There was an early post that had suggested to open 'ALL"
11-13 1NT..Well some of the extreme examples ?? seem extreme.
But , once again , if the system design leaves..no choice..
Why can't you open 1NT with the singleton.
Answer seems to be..It is OK but you can NOT agree to do so..???
Well we know pairs that do open with a singleton, usually an Ace.
So they have an agreement, but if they don't 'admit' to it.. it is OK??

So how tight/specific do you have to be to design a system
where you 'MAY' have to open with a singleton even though
you 'generally' have a balanced hand.

We have 'no agreement' or way to find out about the singleton
unless responder continues on toward slam and subsequent cue
bids might reveal - what else could it be - a singleton.

Too bad I don't live in Europe..

[Vampyr]

pickabidp, on 2015-March-10, 23:36, said:

But , once again , if the system design leaves..no choice..
Why can't you open 1NT with the singleton.
Answer seems to be..It is OK but you can NOT agree to do so..???
Well we know pairs that do open with a singleton, usually an Ace.
So they have an agreement, but if they don't 'admit' to it.. it is OK??

It can hardly be part of their system to open 1NT with whatever shape they have if they require a high honour!

Quote

So how tight/specific do you have to be to design a system
where you 'MAY' have to open with a singleton even though
you 'generally' have a balanced hand.

You are not allowed to do this.

[Lanor Fow]

If there is a known system hole such that you would open 1nt with a singleton because of this. Given the system hole is known I believe this would could as an agreement (implicit if not explicit)

[Vampyr]

Since clubs often have looser system restrictions than tournaments, you might be permitted to play your system at the local if you get permission from the management. You would probably have to pre-alert.

But I am not sure that working on a system that you can play in maybe one club and no tournaments is a good use of your time and effort.

[hrothgar]

pickabidp, on 2015-March-10, 23:36, said:

Why can't you open 1NT with the singleton.
Answer seems to be..It is OK but you can NOT agree to do so..???
Well we know pairs that do open with a singleton, usually an Ace.
So they have an agreement, but if they don't 'admit' to it.. it is OK??

yes

Quote

So how tight/specific do you have to be to design a system
where you 'MAY' have to open with a singleton even though
you 'generally' have a balanced hand.

As soon as you "design a system", this becomes systematic and therefore is is not sanctioned.

It's clear that you don't like the way things work (Welcome to the club), however, I don't know how people can be any more clear about the existing regulations.

Those are the rules. Either learn to live with them or get your local tournament organizers to grant an exception.