[gnasher]

Using screens, if there's a delay on the other side of the screen you can sometimes tell from the auction that it's more likely to be one side than the other. For example:

You're sitting East, so the screen is to your left. Your partner opens and you have the uncontested sequence

1♠-2♦  (game-forcing)
2♠-3♠
4♣

The 4♣ bid appeared after some delay. It's possible that the delay was because LHO chose to ask a question before passing, but the most likely reason for the delay is that partner was considering what action to take. Assume for the sake of this discussion that we think it's 95% that partner was thinking.

In this situation, are you constrained by the probability of UI? Note that Law 16B1 speaks of "unmistakeable hesitation".

If you're constrained in that situation, what about in another auction where there's a 60% chance that partner was thinking? Where do we draw the line?

[pran]

IMHO when playing with screens neither side should be accountable for such delays unless the probability that one particular side has a BIT is overwhelming.

I don't know where the line is usually drawn, but comes to my memory the situation in an European championship played in Reykjavik years ago where a Board was played out in the Men's room!

Near the end of the auction both players on one side of the screen needed to go to the room, and while there one of them received full information on Trelde's asking bids which had been used, and also the statement that if the other partner's answers were satisfactory they would end in a small slam. The outcome of this slam would only depend on who held the King of Diamonds. If it was our friend here he would make seven on a simple squeeze, otherwise he would make six. Our friend here understood and saw this clearly.

Back at the table they quickly completed the auction and received the opening lead. Then the aquestion: "Do you have the King of Diamonds", the answer (I don't remember whether it was yes or no), and the hands were returned to the board while the result was recorded. The other two players were undeniably astonished by this "claim".

[aguahombre]

Of course you are constrained by the high probability of partner being the one who caused the unmistakeable delay. But that should not be a problem in the auction you gave, as long as your continuation is consistent with your own holding.

This is a classic position in a 2/1 auction. Neither hand has limited itself, and a Gnasher will know the meanings of the 3 possibilities from which partner chose: 4S, 3N, and a control bid -- and will know which of 3N or the cue was "serious/non-serious" by agreement.

Your constraint would be to assume that after a B.I.T. Opener came up with the correct systemic bid for the strength of his hand, and to continue on that assumption. Be glad he didn't bid 4S after the hesitation, and that you don't have significant extras which would continue over that; for, then, you might have had some explaining to do.