awm, on 2012-March-04, 15:45, said:
Here's what I play by advancer after the penalty double and responder's pass/redouble:
Pass = 5+ points, not a hand with a huge amount of shape though; however if responder's pass/redouble was forcing then pass with any 0-4 hand w/o a suit too
2♦, 2♥, 2♠ = natural, five-card suit, at best about 5 hcp
2♣ = if opener's partner made a non-forcing pass or redouble (i.e. "to play") then 2♣ here is a scramble and could be on any flat hand
2♣ = if opener's partner made a forcing pass or redouble, then 2♣ is natural, five-card suit, at best about 5 hcp (same as 2♦♥♠ above)
2NT = any decent 5/5 hand (wants to bid our own game)
3x = natural six-card suit, better hand for declaring than defending (i.e. points in suit etc)
If responder bids something that is natural (i.e. 2♦ to play, or 2♦ diamonds and a major) then our first double is takeout (whether by opener or responder) and pass is not forcing. Bidding a new suit at the two-level shows 5+ cards there and is constructive and NF (like 5-8). If responder bids something that is artificial (like a transfer) then double by advancer is just "cards" and creates a forcing auction.
In general after 1NT-X-Pass-2♣ (scramble) the doubler will bid a five-card suit of his own if he has one. Otherwise he will fairly often pass (it is normally assumed that 2♣ has four or more clubs even though it easily might not) and we can run later if doubled. Or he can bid a chunky four-card suit etc.
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Apologies to mgoetze, but I think it is pretty bad to play "notrump systems on" in this sequence. The issues include: (1) Notrump systems are designed towards game bidding, whereas on this auction we usually want to just pass and defend if we have an invite or better and we need more ways to scramble on bad hands including those without a major suit (2) Notrump systems are designed to work facing a balanced hand, whereas here doubler can have all sorts of shapes (3) Transfers are designed to put declarership in the stronger hand, whereas here it is fairly often better to have the notrump opener on lead anyway so that he has to lead away from his honors.
I think it's really bad to play anything that means you bid on a flat yarborough, it means you never take a penalty when partner has the really juicy hands.
I've recently had:
Flat 25 count - partner had flat yarborough, we go off if partner pulls, took 300
AKQJxx, AKx - opposite a jack - we took 8 tricks for 500 against a part score
The really juicy penalties out of 1Nxx are where they have the values to be in it, but you've doubled off something like the second hand here, you lose much of the upside of a penalty double if you pull these off bad flat hands.