lamford, on 2019-January-07, 07:15, said:
On the first point, the principle is that one judges what would have happened with screens in most UI situations. At least on the 20 or so ACs I have been on.
When screens are in use, there are a number of differences regarding disclosure. Players explain their own bids to their screenmates, and questions/answers necessarily have to take place twice.
But there's nothing in the Laws that supports the notion that we should expect everything to happen equivalently without screens. We don't expect players to cover their ears while partner is asking a question. They're allowed to hear the question, they're just not allowed to use the question itself to influence their actions.
Here's another way to look at it.
When I was in a child, some teachers would chide students for giving terse answers to questions. If they asked asked something like "Is X true?", you were expected to answer "Yes, X is true" (and perhaps continue with "because ...") rather than just "yes".
Now let's translate that to the Q/A with an opponent. You could ask "Does that show spades?". The opponent could answer simply "yes", or they could answer, "yes, that shows spades". For the purposes of deciding what the partner of the asker is allowed to know, should the form of this answer really make a difference? If the terse answer is given, does the partner really have to ask "Yes to what?" so he's allowed to know that they have spades?
The way this particular UI law is intended is that partner isn't allowed to infer that
you care about spades from the question. And the Law about asking solely for partner's benefit means that you're not allowed to ask the question if you don't really need to know the answer, but think partner does and they wouldn't ask the question themselves for some reason.