ACBL. Matchpoints. Club game. NS is a C pair (both NLM) of decent skill who play together occasionally. (In fact, they finished first overall this day.) W is an accomplished A player (4000+ MPs) and E is B. Not a regular partnership.
The auction went P-P-1♥-2NT. At that point, E asked S what N's bid meant and (surprisingly to everyone but S) was told it was ♠ and a minor. E continued with 3♦, which she (on my inquiry) thought showed a limit raise in ♥. The hand was passed out and EW was down 5. Thats when I was called as N correctly alerted EW to the misinformation at that time. My later discussion with W indicated that he did not understand the 3♦. He was perplexed by the explanation his side had received and was in a quandary since he considered his rebid to be 3♠ which was taken away from him. While I didnt specifically ask this, I presume that he must have concluded that E had a ♦ suit - they were told that N had ♠ and a minor, so the minor must be ♣ since E bid ♦. Since he could tolerate ♦, he passed. E said that even given the correct explanation, she still would have bid 3♦ as she believed it showed a good ♥ raise. (Not sure why she asked, then.)
If W had been given the correct information all along, as an accomplished A player, Id like to think he would have figured out that Es ♦ bid must have shown ♥ support or something other than a minor that the other side had bid. If he did, he would have bid 3♥, ending the auction. However, even during my inquiry, he was not aware that 3♦ showed a good ♥ raise. He was considering a ♠ rebid but didnt feel he could believing N had 5 ♠ behind him. If he had accurate information about the 2NT overcall, thinks E has ♦ (or ♠ but not ♥) and then bids 3♠, E has to bid again. W knows E is a passed hand but E now thinks W has a stronger hand. I think 4♥ would be the right bid for E but 4♠ would be a good bid as well - a 5-3 trump fit generally isnt considered as good as 4-4. Now we have the possibility of 4♥ off 2, or 4♠ off 3. I think most S players would double 4♥ which probably gets pulled to 4♠, so maybe 4♠ off 3 is a possible adjusted score. Also, some with whom I have discussed this hand believe that EW get no relief - passing 3♦ is SEWoG and the table result stands. I disagree since his decision to pass was influenced by the misinformation. The other consideration is whether Law 12C.1.© applies here. While we didnt poll any other players, I suspect there would be a variety of answers and possible adjusted scores. 3♥ off 1 isn't that easy to accomplish and maybe off 2 is a more likely result.
While I keep coming back to 3♥ off 1 or 2, (off 1 is what the club manager and I decided) although I am concerned about what happens if he doesnt figure it out. I still feel that the misinformation led to his poor decision and that an adjustment is warranted based on that fact alone. The fact that the adjusted score we assigned evenly splits the matchpoints between the pairs seems to fit exactly what the law was designed to do. Factoring in some likelihood of 3♥ off 2 and 4♠ off 3 may get us to the right answer.
Thoughts appreciated.