There's been much discussion of 4
♦ versus 4
♥, but not much discussion of:
mtvesuvius, on 2011-August-16, 01:29, said:
Partner's pass is in theory a relay beginning a spiral scan. Redouble would have been business. This means that partner couldn't be bidding keycard in clubs, otherwise they would have redoubled for sure. Therefore it now seems like AI that partner has messed up someplace.
(assuming this is still relevant, i.e. that 4
♥ was enforced and partner's desire to bid 4
♦ is UI)
If pass of 5
♣ is really impossible, wouldn't partner know that too? Maybe he's trying to use it to get to play 5
♣ but not redoubled.
I feel like if you want to argue strongly that your partnership always uses the strict meanings of bids according to your system notes, and that the pass really is spiral scan, with partner certain of the small slam and hoping to get to a grand (win 6 vs 5
♣xx if you get to the grand, lose 2 if you get to the small and make 6, lose 6 if you get to the small and make 7), you can be allowed to make your normal spiral scan response. If you want to argue that it's impossible partner wants to spiral scan, I think pass is a logical alternative. I can't see an incorrect spiral scan response being allowed over the normal one in the first case or over pass in the second case.