pretzalz, on 2011-September-25, 23:34, said:
The most likely reason for South failing to alert 3♥ must surely be because he or she did not think it was alertable (i.e. strong and natural). The failure to alert has done two things:
- woken-up North as to her misbid; and
- conveyed to North that South is treating 3♥ as natural, in which case 4♥ takes on a completely different meaning to what it would've meant opposite a splinter.
North has UI that South has a different interpretation of the 3♥ bid to what North initially intended and is ethically bound to avoid selecting actions suggested by that UI when other logical alternatives exist. Generally speaking, one will meet one's ethical obligations by bidding one's hand as if no UI had been transmitted (including not being woken-up to your earlier misbid) but even then you may still be subject to an adjusted score if some other logical alternative within the serious consideration of your polled peers was going to be less successful.
There may be situations where partner's bid opposite your non-alerted, but intended artificial, bid is sufficiently weird that it can only mean partner has misinterpreted your bid which would be AI. For example, a 5X response to a 4NT bid which was intended as quantitative would carry the reasonable AI that partner took it as Blackwood and you would be ethically able to proceed on that basis even if 4NT was alerted and described as Blackwood contrary to your original intent. We might be able to throw a lifeline at North here if it can be established that South has no idea about cue bidding and this is a fact known to North, as in that case 4♥ couldn't really be anything other than a natural suit and would legally wake-up North to the misunderstanding.
Perhaps a good question to ask North is, "when you bid 6♠ did any other potential bids cross your mind and why did you rule those out?"

Help
