I hate it when my computer crashes and loses all my work. Let me try again.
If this was online, it probably wouldn't have been posted in the "offline bridge" forum.
I would not assume there were any alerts, nor that any were required.
Jillybean is right - this is clearly a case for Law 16. South's explanation gave North the UI that he had misbid. He's not allowed to use that information. When West asks and hears that 2
♣ is natural, and then bids 2
♦, it seems to me he's just thinking of competing for the part score. Foolish, perhaps, given the opponents have most of the points, but players do foolish things sometmes. I wouldn't call the question about 2
♣ "stupid", either, even if there was no alert. If there's no requirement to alert, how else is he gonna know what it means? Okay, he gave NS a chance to recover, but they can't legally do that by using UI. So did they? Maybe.
East may have a case for a score adjustment, but he has no business accusing North of "unethical behavior". That's just adding fuel to the fire. Dig out the law book, show North why he shouldn't have done what he did, but don't call him unethical, or a cheat. As my mother used to say "two wrongs don't make a right".
"Cheat" carries a connotation of deliberate action. If a player doesn't know he's violating the rules, is he still cheating? Even if he is, the laws of bridge aren't designed to call people cheats, they're designed to provide redress for damage, whether there was cheating or not. Same for "unethical". The laws of the game define its ethics - "unethical behavior" also carries a connotation of deliberate violation of the rules, which is hardly possible if you don't know what you're doing is illegal. No, leave that whole can of worms alone (in a tournament environment, when you have
clear evidence of cheating, it's a different story. Then you should report it - privately).
The question was raised whether the NOS should be entitled to redress, given their poor defense in the play. Did they "fail to play bridge"? Were their actions "irrational, wild or gambling?" Doesn't seem so to me, so I wouldn't deny them redress on that score.
There is no obligation on South, who has no UI, to bid in accordance with her explanation of North's bid. There might arise, in some jurisdictions, a question of fielding a misbid, I suppose, but it seems unlikely in this case.
It isn't South's 3
♥ bid which should be called into question here, but North's 3
♦ and subsequent 4
♥ bids. North has UI, so he must avoid using that in choosing his calls. If the UI may have influenced him, (and if the opps were damaged thereby) then we should adjust the score. If he didn't use UI in making those calls (maybe there was no LA, or the UI didn't suggest those calls. Please note that I said
maybe; I haven't analyzed that question) then no score adjustment is warranted.
If, in a given situation, a partnership's agreeement mean there was no logical alternative to a call made by a recipient of UI, then he has done nothing wrong, and there should be no score adjustment or other penalty.