Club Game. ACBL. Limited masterpoint section (499).
I was called to the table and (limited by our software at BBO) W had bid 2♦ over S's 2♠ overcall. Following W's insufficient bid, N alerted her partner's 2♠ bid, which was described as showing ♠ and a minor. At the table, I ruled that because of N's failure to alert, W could withdraw her insufficient bid without penalty (L21B.1.(a)). After considerable pause for thought, W passed, as did N. E then bid 3♥. S was concerned that E had improperly used information from W's withdrawn call. While in the given auction E clearly had such a bid, I advised S that since E-W were the non-offending side, information from the withdrawn call was authorized (L17D.1.). S passed, W raised to 4♥ which was passed out. E made 5.
After additional consideration, I am concerned that my ruling may have been improper. L21B.1.(a) gives the director the ability to allow a player to change a call when "the decision to make the call could well have been influenced by the misinformation" (failure to alert, in this case). However, the failure to alert did not cause the insufficient bid. Had I told W that she could bid freely but that her partner would be required to pass (doubting their agreement would have 3♦ being a transfer to ♥ or that they had anything else in their bag of tricks that would meet the requirements of L27B.1.(b), thus taking any recovery away), she may have bid 3♥, or even taken a chance on 3 NT, which also makes. Regardless, I can't see giving the contract to S at 2♠, which should go off one. In polling experienced players and directors at the game, all believed that the failure to alert by N was paramount, allowing W to recover without penalty from her error. I'm not convinced. However, I don't know what the adjusted score for N-S should be, although I need to come up with one if I am going to call a L82C. error on myself. The best for N-S would be 3♥ making 5, but I tend to like 3 NT by E making 3.