[Coelacanth]

We had this "auction" yesterday in an ACBL sectional Swiss:

---

You can probably predict where the issue arose.

1: 2NT was intended to show the minors but was explained by East (upon questioning from North at his turn) as natural
2: 3♦ was intended by East as a transfer (systems on after natural NT overcalls).

5♣ went quietly two off, +100 NS.

MI issues: It turns out that East and West disagreed as to the correct meaning of 2NT. (In discussion after the hand, they agreed to play it as for the minors). So East's explanation to North (I was North) was MI. Had the call been explained as showing the minors, I would likely have bid 3♠, and it is by no means clear where the auction would have gone from there.

UI issues: I thought at the time that West's failure to pass over partner's 3♦ was blatant use of UI. If you make a bid showing the minors, and partner prefers ♦, why would you ever bid on unless you had an enormous hand? (he did not have such a hand). However, 3♦ is a likely make, so NS were clearly not damaged.

3♠ for NS may or may not have been on, but 4♠ certainly would have failed. I think it's unlikely that West, with 0256 shape, would have sold out to 3♠ anyway. Considering the above, I just scored up +100 and went on to the next board.

Should I have summoned the TD?

[aguahombre]

"Should I have summoned the TD?"

Probably. But, I understand your decision not to do so.

Depending on East's hand, and their real agreements on follow-ups if 2N is known to be the minors by both players, I can picture this auction exploding to the slam level without any convention disruption known.

[barmar]

In ACBL territory, "everybody" plays it as natural. There isn't even a place for this bid on the ACBL CC (the place for Unusual 2NT specifically says "Jump to 2NT"), and I can't recall ever discussing this with a new partner. So without any special discussion, I think East's explanation is correct, and West misbid.

Yes, it's technically undiscussed, but that's because it generally doesn't need to be discussed.

[aguahombre]

barmar, on 2011-November-08, 01:02, said:

In ACBL territory, "everybody" plays it as natural. There isn't even a place for this bid on the ACBL CC (the place for Unusual 2NT specifically says "Jump to 2NT"), and I can't recall ever discussing this with a new partner. So without any special discussion, I think East's explanation is correct, and West misbid.

Yes, it's technically undiscussed, but that's because it generally doesn't need to be discussed.

I guess you are choosing to ignore the OP. They had agreed to play 2NT as the minors.

[Coelacanth]

aguahombre, on 2011-November-08, 05:50, said:

I guess you are choosing to ignore the OP. They had agreed to play 2NT as the minors.

They only agreed AFTER the hand in question was over.

I agree, that absent any discussion, natural would be the correct interpretation, and that this is a misbid and not MI. West, however, believed that they had discussed it and agreed minors; East did not recall having any such discussion.

[aguahombre]

"It turns out that East and West disagreed as to the correct meaning of 2NT. (In discussion after the hand, they agreed to play it as for the minors). So East's explanation to North was MI."

The way I read the above is that after the hand, they agreed that "for minors" had been their prior agreement; and the OP confirms this inpertretation by stating explanation was MI, not correct. It certainly makes a big difference in whether a ruling would be appropriate.

If they did have the prior agreement (which they admitted after the hand), West is clearly using UI and it is anyone's guess (with screens) how high they would have finally landed in a minor.

Here, North asked about 2NT ---giving West the UI. If North hadn't asked, then East would have the UI issues when his 3D bid was not alerted (whether explained or not). But, the auction would have been over in 3D without North's question about an unalerted bid. So, N/S seem to have benefitted by that...serendipity.

[bluejak]

Coelacanth, on 2011-November-07, 11:15, said:

Should I have summoned the TD?

Of course. I really cannot understand why you did not. The opposition have committed MI probably and used UI possibly. Why on earth would you not call the TD?

[barmar]

aguahombre, on 2011-November-08, 09:39, said:

"It turns out that East and West disagreed as to the correct meaning of 2NT. (In discussion after the hand, they agreed to play it as for the minors). So East's explanation to North was MI."

The way I read the above is that after the hand, they agreed that "for minors" had been their prior agreement; and the OP confirms this inpertretation by stating explanation was MI, not correct. It certainly makes a big difference in whether a ruling would be appropriate.

The way I speak, "they agreed to play" refers to the future; if they were discussing an existing state, more correct phrases would be "they agreed that they play" or "they had agreed to play". However, I recognize that people don't always use the precisely correct terminology when writing (these nuances are not exactly obvious), so the latter could have been intended. It would be helpful if the OP would confirm one way or the other what was actually agreed.

And while you may be correct that stating that the explanation was MI confirms your interpretation, it could also indicate that there was lots of confusion that resulted.