Inverted Minor Sequences

[uva72uva72]

My link

 

Match Points, ACBL robot individual.

Is there a trove of system notes on inverted minor raises somewhere? The notes available under the "GIB CC" tab are minimal; and when I consult the system notes during auctions, the bids all seem to mean the same thing, viz. "3+ cards in minor, 12-14 HCP." In the examples I've posted, the robot's rebid of 3♣ is given almost exactly the same explication as its 2♣ bid. If that's intentional, then why would the North robot bid on over 2NT? Jxxx can't be expected to play well opposite 3 cards, which the system notes allow as a possibility for South's bid of 2NT.

 

The earliest info on inverted minors that I am aware of was made available in the the Kaplan-Sheinwold system book. According to that system, after the inverted raise, opener rebids 3 of minor with an unbalanced min, bids 2 or 3 NT with 3 cards in the minor opened (depending on whether opener wants to be in game opposite a minimum raise), and with 4 cards in the minor opened bids the lowest ranking stopper. As I recall, responder only rebids the raised minor with length (5+ cards) and a minimum raise and otherwise cooperates in the hunt for 3NT. This may not be the ultimate approach, but it seems preferable to guessing what contract to play knowing only that opener (or responder) has 3+ cards (or 4+cards) in the suit and a balanced hand.

[iandayre]

It has become standard that a jump to 3NT over an inverted minor raise shows 18-19, i. e. a hand that would have jumped to 2NT over a 1M response. With a 14 count that wants to be in game, you bid a major then 3NT your next call.

 

With the actual hand, you should show your stopper with a 2S rebid, promising no extras. The proper GIB rebid is 2NT (not sure that is what it would actually do) and you would of course pass.

 

I certainly would agree that GIB should pass 2NT on the actual auction as well.