[gnasher]

Codo, on Jul 16 2010, 06:42 PM, said:

Maybe I asked the wrong question: On which hands do you win with your approach.  Where do you think it is better to find the diamond fit before you find the major fit?

I wasn't particularly arguing for allowing a major in 1♦-2♦. Mainly I was disagreeing with the assumption that it's important to be able to show stops over 2♦.

[nige1]

Codo, on Jul 16 2010, 06:42 PM, said:

Maybe I asked the wrong question: On which hands do you win with your approach.  Where do you think it is better to find the diamond fit before you find the major fit?

gnasher, on Jul 17 2010, 05:34 AM, said:

I wasn't particularly arguing for allowing a major in 1♦-2♦.  Mainly I was disagreeing with the assumption that it's important to be able to show stops over 2♦.

IMO Gnasher hints at the main argument for allowing an inverted minor raise to include a 4 card major.

• 1m - 1M sequences cover a variety of hands that need exploration whereas
  
• 1m - 2m sequences have spare capacity that you may as well exploit. Furthermore
  
• Support with support is a maxim worth considering.

[jdonn]

Codo, on Jul 16 2010, 12:42 PM, said:

Maybe I asked the wrong question: On which hands do you win with your approach.  Where do you think it is better to find the diamond fit before you find the major fit?

Suppose it goes, with you (and most people including me most of the time, unfortunately) as responder,

1♦ 1♠
2♣ 2♥
2♠ 3♦

You have shown a game force with 4+ spades and 4+ diamonds, I have shown a game force with 5+ spades and 4+ diamonds. I think that makes things quite a bit easier although I'm not going to bother constructing an entire hand. There are many such auctions like this, another being

1♣ 1♥
1NT 2♦ (game force)
2♥ 3♣

I don't think most of the gain comes from showing a minor suit fit before a major suit fit, I think it comes from clarifying that if responder has a game force with support for the minor on all auctions like this, he promises 5+ of his major.

I also think something seems very natural about it. When you have 4 spades and 5 clubs and a game force and partner opens 1♦, you show clubs then spades. Why should it be less important to show clubs first when partner actually opens in clubs! It actually seems silly that most people are more interested in showing the minor partner didn't open first than they are in showing the minor he did open.

[gordontd]

I played that inverted minor raises could contain a four-card major with one partner. This was in the context of a weak-NT system, so a 2NT rebid was forcing.

Following from this was:

1m-2m-2M showed an unbalanced hand

1m-2m-2NT showed a balanced 15+ and could contain a 4cM

1m-2m-2NT-3m asked for 4cM

After 1m-1M any invitational+ preference to the minor showed a 5cM with four-card minor support.