[hammberry]

Matchpoints; none vul
LHO opens 1D, partner overcalls 1NT; RHO doubles
we ended in 3S, for the best possible score
partner held: AQxx, --, KQJxxxx, xx

What arguments could I use to suggest that 1NT was misguided?

[Hanoi5]

Your partner is not balanced. Your partner's hand is not NT oriented. Your partner doesn't have a 16-18 HCP's hand. Your partner does not have a 1NT overcall.

[the hog]

Hanoi5, on 2012-September-27, 20:56, said:

Your partner is not balanced.

Well that is definitely correct.

[SteveMoe]

Probaly a good idea to review:
1) Overcalling at the 1 level with a 4-card major,
2) Passing then bidding RHO's minor as natural.
Might want to remind partner that some open 1♦ on 2 (Precision), 3 (4=4=3=2) and 4. Who owns the ♦ suit anyway?
IN means we stop the suit (not own the suit) with 15-17/8 balanced HCP.
Just a thought.

[PhilKing]

Hanoi5, on 2012-September-27, 20:56, said:

Your partner is not balanced.

And he doesn't have a balanced hand, either.

[billw55]

hammberry, on 2012-September-27, 20:42, said:

What arguments could I use to suggest that 1NT was misguided?

Bridge is a game of communication. Certain bids tell partner certain things about your hand. When you make a bid that has a certain meaning, and your hand bears no resemblance to that meaning, then you are misleading your own partner. This will often (but not always) lead to bad results, and even more often cause partner to lose trust in you.

1NT shows a particular type of hand. You don't have that hand, not even close. So don't bid it.

[kenberg]

Some years ago the opponents asked my partner to explain the meaning of my bids. She replied that she had no idea what I was doing, and that I seemed to be playing with myself. That seems to apply here. The general idea is that bidding is a partnership activity, something two people do together, and it would be good if you, the partner, had some idea of what he has in his hand when he enters the auction. Of course an insane action might work out well. Now and then, once in a while. That doesn't mean insanity is a good policy.

[ArtK78]

hammberry, on 2012-September-27, 20:42, said:

Matchpoints; none vul
LHO opens 1D, partner overcalls 1NT; RHO doubles
we ended in 3S, for the best possible score
partner held: AQxx, --, KQJxxxx, xx

What arguments could I use to suggest that 1NT was misguided?

Well, let's see.

The 1NT overcall of 1♦ represents a hand which:

1) Contains 15-17 HCP or 16-18 HCP or so, depending on your partnership's agreement.
2) Has balanced or semi-balanced distribution; typically 4333, 4432, or 5332.
3) Has diamonds stopped.

Your partner's hand does not contain 15-17 HCP and is not balanced or semi-balanced. It does have diamonds stopped (and then some).

Others have already mentioned that bridge is a game of communication and that when partner represents a hand with certain characteristics and he does not have that hand it will lead partner astray, often resulting in a poor score. For example, on this hand, if you had long hearts (certainly a possibility given partner's void) you would be well within your rights to insist upon playing in hearts. That would not have worked out very well in all likelihood.

Fortunately for you on this hand, you wound up on your feet. I am sure the opponents were not happy. So, while you may have gotten a good score on this hand, your partner's offshape and understrength 1NT call probably generated some ill will, which is also not a good thing.

[Zelandakh]

I suspect the best way of getting the desired message across to partner is to wait a few weeks and then give them a weak hand with 5 hearts to bid opposite this one after the start (1♦) - 1NT - (P).

[ggwhiz]

Zelandakh, on 2012-September-28, 07:44, said:

I suspect the best way of getting the desired message across to partner is to wait a few weeks and then give them a weak hand with 5 hearts to bid opposite this one after the start (1♦) - 1NT - (P).

Give them a strong hand with long hearts too. After they bid it tell them this was the 1nt overcall and see what they think of that. If they don't agree with the 1nt call you can go over the reasons why as others have pointed out.

If they do agree with it give up and punt.