When an opponent makes an artificial bid, it affects the meaning of some of your bids.
Let’s say that left-hand opponent opens 1NT and RHO responds 2. If 2 is natural (the opponents may play a weak notrump), your double is takeout, short in hearts, and a 2 overcall is natural.
If 2 is a transfer to spades (Announced), your double is lead-directing, showing length and strength in hearts, the artificial suit, and 2 is artificial, typically a three-suited takeout of spades, RHO’s real suit.
This is a standard defense against transfers and shouldn’t require much discussion between experienced players.
The main point is to be prepared. In this series, I plan to propose simple, mainstream defenses to everyday artificial bids, occasionally offering a more detailed option. The goal for every regular partnership is to have a workable defense in place and not be caught by surprise. There is only a small difference between adequate methods and optimum, but there is a huge difference between adequate and none.
You are South in this sequence; what does double mean:
East’s 2 support cuebid generally shows a fit for opener’s suit and at least limit raise values. It is sensible for South’s double to indicate a raise to 2. It is important to disclose support, both as a basis for further competition or to guide the defense.
How would you treat the next two sequences? You are South in No. 2 and North in No. 3:
* Fourth suit forcing
In each sequence, the double shows length and strength in the fourth-suit. It is lead-directing and, potentially, very useful. Don’t double with A-K-5-3, however, unless you want to achieve immortality by scoring a very unusual number, such as minus 1240 for 2 making an overtrick, redoubled and vulnerable. Yes, it can happen.
The safeguard is to hold a strong five-card suit (or longer) such as A-Q-10-x-x.
If you double an artificial bid at the four-level or higher, however, such as a control bid or a Gerber or Blackwood response, A-K-5-3 is fine. Not only are the opponents a level higher, but when they have found a fit and are searching for slam, they’re most unlikely to take a sudden detour and play in a doubled cuebid.
In sequences No. 2 and No. 3, where they haven’t yet found a haven, an unwise double may offer them the keys to the Ritz penthouse. There is a subtle difference be-tween doubling a two level transfer response and Stayman.
In these sequences, you are South:
After the transfer in No. 4, opener knows the degree of fit with responder’s suit. Holding a doubleton spade, West tends to pass, which keeps a possible contract of 2 doubled in play. If East has three hearts to two honors, only five spades, and perhaps 8-plus HCP, East can pass and shoot it out in 2 doubled. With more strength, East can redouble for business. Either way, South is in big trouble if he has chanced a double on four medium hearts in a modest hand.
In No. 5, West often doesn’t know whether his side has a major suit fit, particularly if 2 didn’t promise a four-card major (when East’s 2NT response may be a transfer). Accordingly, West usually bids 2 or 2 with four to probe for a fit, or perhaps 2 to deny both a major and a club stopper. Either way, South is off the hook if he has made a speculative double.
The bottom line: If you are inclined to gamble a lead-directing double, you run a smaller risk against Stayman than transfers.