Excellent question

[Curls77]

A second before pulled to IAC spur teams, a member asked his table:
"Does anyone know what redouble over a stop showing bid doubled means in inverted minor?"
What a good question!! I am not sure most of us that do play inv minor ever tought or discussed this. What do u say?

[Masse24]

I would want to see the auction. But . . . if by opener in an auction like this:

1 - (P) - 2 - (P)
2 - (P) - 2 - (X)
XX -

I would think it a Business Redouble. A willingness to play it there. I suppose I could come up with an artificial meaning, something like, "I do not have a stop, how about you?" But lacking that, business seems like the natural meaning.

Alternatively: "I want a new partner."

[wackojack]

I assume in the following auction
1♦  -   (p) - 2♦(i) - (p)   (i) Inverted minor suit raise 9+
2♥(ii) -(p) -  2♠  -  (x)(iii) (iii) Presumably lead directing for ♠, likely 4 card suit with good values.
(xx) -(p)  - ?

(ii) The meaning of the redouble comes down to what type of hand does the rebid of 2♥ show. Here is what Max Hardy has to say:
1.   Opener rebids 2NT to show a balanced hand with minimum values (12 to a bad 13) and promises stoppers in both major suits.
2.   A jump rebid of 3NT shows a balanced 18-19
3.   A rebid in a suit at the 3 level is a splinter.
4.   All other hands show “stoppers up the line” 

Thus 2♥ shows either a balanced 12-bad 13, with a ♥ stop and no ♠ stop.  Or a balanced good 13-14 both ♥ and ♠ stop. 

So, what should we infer about the redouble assuming it was done intelligently?  The redouble gives opener the opportunity show partner a good 13-14 with a ♥ and ♠ stop. This gives partner an excellent basis to decide the final contract. 

If opener does not redouble then what should pass and 2NT show? I am not too sure. Perhaps 2NT would have the same meaning without the double.  What about pass?  4432 distribution with very good spades suggesting to play in 2♠ x?  A bit dangerous perhaps.

Further to the subject of inverted minor suit raises.  In absolutely 100% of the times that I have kibbed when this convention has been used there has been a misunderstanding with a bad result.  Further to this I believe that 1m-2m 9+ is retrograde.  For inverted minor suit raise to work you more levels of raise.  This I play with whomever is interested:

After 1♣ with 5+ ♣s and no 4 card major not suitable for a no trump response:
2♣ = 11 +, 2♦ = 8-10, 3♣ = 5-7. 
After 1♦ with 4+♦s and no 4 card major not suitable for a no trump response:
2♦ =11+, 3♣ = 8-10, 3♦ = 5-7

The jump shift showing this intermediate raise gets rid of the temptation for many in making the thought to be strong hands thus eating up bidding room and making it unlikely to find the best contract.     

btw I also like to play that 1 open guarantees 4 cards making inverted minor handling much easier.  I know that Todd does not like this. 

I would be happy NOT to play inverted minors otherwise.  I dread getting a hand with a minor raise in iac.       

[kenberg]

My first thought about "what does the XX mean?" was that I have never discussed it with anyone, and that has never mattered because it has never come up. Well, my very forst thought was that I don't understand exactly what is being asked. I could imagine
1m - pass - 2m - pass
2M -    X      XX

or

1m - pass - 2m - pass
2H -  pass - 2S -    X
XX

I had assumed the first, others seem to be assuming the second.


So let me go with the first for a moment. It seems like it won't much happen, and it hasn't. Just take

1m - pass - 2m - pass
2M -    X 

What does the doubler have? He lacks the values to bid 1M over my 1m but now wants to double my 2M? The double is fr a lead no doubt but he cannot have, or is very unlikely to have, a strong  five card suit. If he has a strong four card suit I appreciate his letting me know about that and I will alter my bidding and play accordingly. Now if i have a stopper in M and my lho has a good four card holding in M it seems unlikely that partner is also going to have a good holding in M so maybe XX should just be a general game force, or perhaps even a game force with a shortness in M.

But really the situation has never come up in the first auction, nor do I recall it aver coming up in the second.

This all relates to Jack's comments, namely that there are more basic issues to discuss when playing inverted minors. I recall reading an expert opinion that inverted minor raises are a modest plus for pairs that have discussed the details and a modest or sometimes substantial minus for pairs that have not discussed the details.

For example, this is taken from BWS:

"After a strong single minor raise, opener can: (1) show willingness to play in three of his minor by bidding it; (2) bid two notrump natural (but the bidding is forced to three of the minor); or (3) bid a new suit (after which the bidding may still stop at three of the agreed minor)."

How many  pairs have discussed even this much? So 1m-2m-2NT is forcing for BWS. I am pretty sure that the bots play this auction as non-forcing. I play it as non-forcing with my usual f2f partner. I think playing it as forcing is probably better, but that requires some discussion also.  My point is that the auction 1m-2m-2NT arises often, the XX auction I cannot recall ever arising.

I  have had reasonably decent results with inv minor auctions.  My preferences for 1 - 2 :

My 2 call could be on four cards, but only if I have game forcing values. If I have more modes values, maybe 10-12 highs, I will have five diamonds and I expect my next call to be 3 , however 1 - 2 - 2M - 2NT is a possible continuation and is passable.

If the suit is clubs rather than diamonds, it's pretty much the same but now I might want a little more shape or a little more strength.

Also, the auction 1m-2m-3m shows a minimal somewhat shapely hand for opener.

This seems to usually work out ok. BWS plays that 1 - 3 shows clubs and with invitational values. I think, but I am not sure, that the bots do the same. Using 1 - 3 as an artificial raise of diamonds of some particular strength has its merits, but so does the BWS approach.

As to whether the opening 1 needs to show four cards, views have differed forever. My preference is that a 4=4=3=2 shape be opened 1 .  I realize it can cause difficulties but having to open it 1 can also cause difficulties. Using the inverted minor raise the way I lie, then when partner opens 1 on a three card holding we might end up in 3 on 5-3 fit but not in a 4-3 fit since, when I have only four cards, I plan on going on to game somewhere.

Short version: There are many different ideas on how to play inverted minors, the most important thing is to talk it through. The meaning of the XX could be fairly far down on the list of things to discuss.

One more thought about opening 1 on three  cards. Suppose the auction begins 1 - 1M - 1NT, a pretty common auction. Partner has four or maybe five diamonds since he clearly lacks four card support for M. Usually it becomes clear early on whether the 1 opening had to be on four. Not always, but almost always. I can't recall the last time it caused me a problem.

[Masse24]

For example, this is taken from BWS:

"After a strong single minor raise, opener can: (1) show willingness to play in three of his minor by bidding it; (2) bid two notrump natural (but the bidding is forced to three of the minor); or (3) bid a new suit (after which the bidding may still stop at three of the agreed minor)."

How many  pairs have discussed even this much? So 1m-2m-2NT is forcing for BWS. I am pretty sure that the bots play this auction as non-forcing. I play it as non-forcing with my usual f2f partner. I think playing it as forcing is probably better, but that requires some discussion also.

One of the questions I ask when agreeing to Inverted Minors is, "Forcing to what?" I, too, prefer to play it forcing to 3m, but it was not that long ago I played that 2NT by either player was not forcing. This treatment is, I believe, the legacy method. It was also standard in BWS2001. I am fine playing it either way. I have had a few people express shock that 2NT is treated as forcing in the most recent BWS.

Curious about how the polling went on that question, I just looked it up. Here are the poll results:
      426. A single minor-suit raise should be forcing to . . .
            A. three of the minor [73]
            B. two notrump [27]

As far as how many pairs have discussed it? If truly a partnership, I would hope all. Though maybe I'm being optimistic.

Like Ken says, there are so many Inverted Minor treatments out there, you never know what your partner is using. I just assume the simplest (and what I assume to be standard) if no discussion.

Jack mentions my disdain for a short club. Yup. It's a trade-off. I prefer my 1 open to promise three. Doing so, I lose little. My 1 opens also promise four plus, but only 97% of the time. Which is good enough for me. 

[wackojack]

Jack mentions my disdain for a short club. Yup. It's a trade-off. I prefer my 1 open to promise three. Doing so, I lose little. My 1 opens also promise four plus, but only 97% of the time. Which is good enough for me. 

Sorry to be picky and getting off Sanya's original question but the other side of what you say is good enough for you is exactly the same as what is good enough for me  NB: My 1 promises a 3+ cards 97% of the time.  That is good enough for me.  The trade off is equal.