Source: ACBL
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When an opponent Alerts an artificial bid, the common defense is to use double as a lead-director. Let’s say that left-hand opponent opens 1 and right-hand opponent bids 3, alerted as a game-forcing raise in diamonds.
If you double 3, be sure to hold both length and strength in clubs; A–K–x is not enough. For one, the opponents may finish in notrump, and a club lead may help declarer establish slow club tricks.
Worse yet, partner’s normal lead from length might have beaten the contract. Second, the opponents may decide to reverse course, pass 3 doubled and make it, outscoring 3NT or 5 undoubled.
A large number of conventions lend themselves to this generic, lead-directing defense, so one size fits most. (Previously, we noted that splinters are a notable exception — doubling a splinter is sacrifice-oriented.)
Bergen raises, quite widely played, offer a wider-than-normal range of defenses. In Bergen, when opener bids 1 or 1, and responder jumps to 3 or 3 (Alerted), responder’s bid is artificial and shows four-card support for opener’s major with limited strength. You can double the artificial minor, lead-directing, or bid 3NT for the minors — have extra values because of the level of the auction — and leave it at that. You might wish, however, to explore other options. For instance, you can cuebid opener’s major, or pass and double on the next round, for example:
A.
West | North  | East | South (You) |
1 | Pass | 3Â | 3 |
 |  |  |  |
B.
West | North  | East | South (You) |
1 | Pass | 3Â | Pass |
3 | Pass | Pass | Double |
 |  |  |  |
Both A and B are sensibly played as takeout of spades — a penalty treatment is unattractive when your spade strength is located in front of their length and they have a nine-card fit. If both sequences are takeout, what is the difference?
It makes sense to use sequence A, the immediate cuebid, as a light but distributional hand, well-suited to a sacrifice, perhaps: — QJ873 K73 KQ1093. Sequence B, the delayed double, is a stronger hand in high-card points, something like: 5 AK74 AK73 K763, when you will be happy to accept a leave-in if partner has a spade trick or two, and little else.
Basically, distributional hands are shown immediately, while hands rich in HCP double for takeout to preserve the defensive option. To help memorize, think of SS–DD: “Shape speaks, double delays.”
If your opponents use preemptive jump raises in the majors with four-card support, as in Bergen, strain to enter their 1/1 – 3/3 auctions. Their nine-card (or longer) fit guarantees that your side has at least an eight-card fit somewhere; this mathematical truth, in combination with responder’s weakness, means that your odds are good on finding a worthwhile contract. Overcalls are natural, double is a strong three-suit-ed takeout, prepared for a conversion, and there are two Michaels options, sequences C and D:
C.
West | North  | East | South (You) |
1 | Pass | 3 | 4 |
 |  |  |  |
D.
West | North  | East | South (You) |
1 | Pass | 3 | 3NT |
 |  |  |  |
Both sequences can be played as Michaels, showing the unbid major plus a minor, with extra values be-cause of the high level. In D, a natural 3NT isn’t very useful, although a case can be made for a long, running minor plus stoppers, a rare hand-type because it is so specific.
3NT for the minors is a possible interpretation, but it reveals a lot to a good declarer if the opponents outbid you — this is the weakness of the unusual notrump. If your partnership likes using 3NT as either natural, minors, or long minor plus stoppers, (pick one treatment), stick with it, but I prefer using 3NT in D as Michaels.
If you must show both minors (extra values), jump to 4NT — at least you gain something from preemption. The Michaels band-type has twice the frequency of the unusual notrump; either the unbid major and diamonds or the unbid major and clubs, versus only diamonds and clubs. Also, Michaels improves your prospects for declaring, especially when you hold spades, as in C.
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