Roman Key Card Blackwood 1430With no agreed suit nor self-sufficient suit bid, standard Blackwood is used
)... do not require an Alert during the auction.
ACBL's theory for not alerting during the auction is that an alert is more likely to "wake up partner" than to help the opponents. You would think that "common ace-asking bids" would not include bids like Kickback, Exclusion, 6-Ace, and Last Train. And in fact elements of 1430 are not known to all club players, such as void-showing and even queen asking. However, in another place, ACBL says that ALL bids over 3NT, starting with opener's 2nd call, are exempt from alerting during the auction. So 1 Either way, the non-common bids are supposed to be alerted AFTER the auction and before play. This is nice, but too late if you would have made, say, a lead-directing double. Your only recourse is to ask for an explanation if any kind of unusual looking bid over 3NT is made. However, a good general principle is to NOT ask for an explanation of any bid until the bidding is over unless you intend to make a bid because by asking, you are giving the opponent a chance to explain his bid to partner in case they were not on the same wavelength. Supposedly, the explanation would be unauthorized information to partner, but the use of such information would be almost impossible to detect much less to enforce.
It is normally considered a mistake to ask for aces/keys when holding a void or a worthless 2+ cards. Say that you have 2 aces and a worthless doubleton. If you bid 4N and partner shows 1 ace, you don't know if his ace is in the suit of your doubleton or not. Likewise, if you have a void, an ace and two king-high suits and partner shows 1 ace, then if his ace is in your void, you have 2 losers off the top whereas if his ace is in one of your king-high suits, you only have 1 quick loser. So if partner bids 4N, he is assumed to have one of the following in each suit: A, Kx, or x -- no voids, no worthless doubletons. When you tell him your number of aces, he knows for sure how many suits he has covered. In 1430, if you don't have the trump K and are also missing two aces, then if partner doesn't shows 2 key cards, you can't bid slam. You also cannot ask for aces if a response would force you to slam. For example, if hearts are the agreed upon trump suit and you are missing 2 keys and partner responds 5D, showing 0 key cards, you can still sign off in 5H. But if clubs are to be trumps, you would be forced to bid 6C over 5D. Mike Lawrence's column in the August 2020 ACBL Bridge Bulletin, page 48, contains an excellent discussion of another circumstance when a player should not use Blackwood - it is when he has all the aces, because asking for aces when you have them all is pointless. Even with a hand like AQ83-AJ743-AK7-4, it is the player with Kings and Queens who can better use the information about aces. With the above hand, Lawrence says North shouldn't bid 4N at any point in this auction because he has lot of holes that need to be filled (while South primarily needs to know how many aces North has). In this case, a cue-bidding sequence was used instead. This deal from the 2019 European Youth Teams tournament is a very fine example of slam bidding combining a number of techniques.
Asking for Aces Only:
4NT Responses can show the number of key cards (Aces + trump King), trump Queen, void.
= 1 or 4 keys counting the trump King
5 = 0 or 3 keys counting the trump King
If responder bids 5 or 5 , he is not able to show the trump Queen.
Asker may bid the next higher non-trump suit to ask about the Queen:
-P. Asker bids 5 if Diamonds are not trumps; otherwise, he bids 5 .
After 4N-P-5 -P. Asker bids 5 if Hearts are not trumps; otherwise, he bids 5 .
Responses:
Bid 5N with the trump Queen and no side-suit Kings. Bid a non-trump suit with the trump Queen AND the King of the suit bid. = 2 or 5 keys WITHOUT the trump Queen
5 = 2 or 5 keys AND the trump Queen
5N = 0, 2, or 4 keys with an unnamed void 6 / / = 1 or 3 keys and a void in the suit bid excluding the trump suit.
bidding 6 lets your partner know that you have a void in Hearts or Spades without going past 6 .
(If the void were in Clubs, you would have bid 6 .)
If Hearts are trumps, you can bid 6 or 6 to show 1 or 3 keys and a void in the suit bid.
Since you will not bid 6 if Hearts are trumps, a bid of 6 indicates 1 or 3 keys and a
void in Spades, the only suit left, without your having to bid past 6 .
5N Asks for number of Kings, excluding the trump King, and implies having all keys.
= no Kings
6 = 1 King
6 = 2 Kings
6S = 3 Kings
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