Monday, December 12, 2005
Your sohl or mine?
2NT has never been a popular contract, and rightly so. In many situations it does not pay to play 2NT as natural. Not because a hand that would want to bid it is not possible, but because there are better uses. Some examples are:
1NT (2♥) 2NT
(2♥) Double (Pass) 2NT
1♣ 1♠ 2♥ 2NT
etc.
Conventions that end in "Sohl" use the transfer principle and use the extra 2NT step in these sequences as a transfer to 3♣ with several hand types. Let's take the first sequence as example. Partner opens 1NT and RHO overcalls 2♥.
2NT is a transfer to 3♣ with either a weak 1-suited hand below opponent's suit (a minor) or some strong variations. With two bids, 3NT and 3♥, and by going through 2NT or not, you can distinguish about wanting to play 3NT with or without stopper in ♥, and with or without 4-card ♠. For suits above opponent's (♠) you have possible ways to show them.
In this version by Ira Rubin all bids are transfers. The weak hands all bid the bid below the suit and then pass when partner completes the transfer. To ask only for a stopper for 3NT without 4-card major, transfer to 3NT with 3♠. Although the number of possible bids to show a suit is the same as Lebensohl, the number of sequences is larger because of more transfer bids. You can show a second suit, or show a suit and then ask for a stopper, for example.
I've actually tried a third variation: Rumpelsohl. Here 2NT shows either a strong hand with ♣ or a weak hand with a suit below that of the opponents. The other bids are as in Rubensohl. These bids have the advantage that all bids except 2NT show a good hand.
Good things: You can also invite in suits lower than opponents except ♣ (opener will decline the transfer with a useful hand), and since you show a good hand, opener can get into to the auction when opponents raise. A big winner is this sequence: 1NT (2♠) 3♦.
Bad things: You lose the sequences where you show Clubs and were planning to bid a suit below opener's after partner accepts. However partner is not barred from showing a big ♣ fit in the same way as after a Lebensohl 2NT. 1NT (2♥) 2NT (p) 3♦ = I can stand 4♣ if that is your suit!
Although the number of sequences in Rumpelsohl (best imho) or Rubensohl is much richer and should be preferred in a regular partnership, the transfer nature of the bids make them more vulnerable for misunderstandings if you and your partner are not clear on which sequences to play the convention. This is why for casual partnerships I suggest you play Lebensohl.
1NT (2♥) 2NT
(2♥) Double (Pass) 2NT
1♣ 1♠ 2♥ 2NT
etc.
Conventions that end in "Sohl" use the transfer principle and use the extra 2NT step in these sequences as a transfer to 3♣ with several hand types. Let's take the first sequence as example. Partner opens 1NT and RHO overcalls 2♥.
Lebensohl
2NT is a transfer to 3♣ with either a weak 1-suited hand below opponent's suit (a minor) or some strong variations. With two bids, 3NT and 3♥, and by going through 2NT or not, you can distinguish about wanting to play 3NT with or without stopper in ♥, and with or without 4-card ♠. For suits above opponent's (♠) you have possible ways to show them.
Rubensohl
In this version by Ira Rubin all bids are transfers. The weak hands all bid the bid below the suit and then pass when partner completes the transfer. To ask only for a stopper for 3NT without 4-card major, transfer to 3NT with 3♠. Although the number of possible bids to show a suit is the same as Lebensohl, the number of sequences is larger because of more transfer bids. You can show a second suit, or show a suit and then ask for a stopper, for example.
Rumpelsohl
I've actually tried a third variation: Rumpelsohl. Here 2NT shows either a strong hand with ♣ or a weak hand with a suit below that of the opponents. The other bids are as in Rubensohl. These bids have the advantage that all bids except 2NT show a good hand.
Good things: You can also invite in suits lower than opponents except ♣ (opener will decline the transfer with a useful hand), and since you show a good hand, opener can get into to the auction when opponents raise. A big winner is this sequence: 1NT (2♠) 3♦.
Bad things: You lose the sequences where you show Clubs and were planning to bid a suit below opener's after partner accepts. However partner is not barred from showing a big ♣ fit in the same way as after a Lebensohl 2NT. 1NT (2♥) 2NT (p) 3♦ = I can stand 4♣ if that is your suit!
Which should you play?
Although the number of sequences in Rumpelsohl (best imho) or Rubensohl is much richer and should be preferred in a regular partnership, the transfer nature of the bids make them more vulnerable for misunderstandings if you and your partner are not clear on which sequences to play the convention. This is why for casual partnerships I suggest you play Lebensohl.
Thursday, December 01, 2005
4- and 5-card majors
This post is a try to give an overview of natural systems with 4- and 5-card majors. Where are the advantages and disadvantages. First let me define a string of minimum opening length. This is the minimum number of cards required for the opening bids 1♠, 1♥, 1♦ and 1♣. For example Standard American would have the code "5533". As a check, these numbers should always add up to 16.
Let's start on one end of the spectrum.
English Acol - 4444
All opening bids on the 1-level promise a minimum of 4 cards. With 4M + 4m usually open the major. There is some freedom here. This system has the advantages that 1M can preempt the opponents and that 1m are well defined, however the disadvantages are that 1m are less frequent and 1M have more bidding problems, esp. after interference.
Dutch Acol - 4444
In Dutch Acol you bid 4-card suits bottom up. This may seem silly and frankly, I think it is. The biggest problem is 1♠, which is either 4♠333 or 5 cards. You want to know which variation is the actual one, especially in competition! Although the string of opening length did not change this is in fact the biggest step between systems! All the others just revolve around one or two distributions.
Swiss Acol - 5443
This is like Dutch Acol but 4M333 hands are opened 1♣. You have the advantage of 1♠ showing 5 cards but not for 1♥, which may have 4 cards if it also has 4 cards in ♠. This makes it harder to find fits in ♥ as partners have no certainty.
SEF, SAYC, 2/1 - 5533
This is like Swiss Acol only the 4♠4♥32 hands are opened with the 3-card minor. Now 1♥ promises 5 cards, making life easier for responder. This means that 1♦ is only 3 cards if 4♠4♥3♦2♣. This gives the same problems as 1♠ in Dutch Acol and 1♥ in Swiss Acol, we keep moving the problem down. Here it is again:
1♦ (2♥) ?
You have 4♦ 2♥ and want to find a bid. Your length in ♦ increases the chance that partner is short, and if he is you know that he has 4♥. So either we have a 4 - 4 fit and they probably have a fit somewhere too, OR we have only 7 cards in ♦ and the same is true for their ♥. Your guess!
Italian 2/1 - 5542
This is like SEF but hands with 4♠4♥3♦2♣ are opened with 1♣. I prefer this method by far over any of the above. Note that we have moved our problem down another step now. However, it is best faced in 1♣, the most shaded of the opening bids even before this problem. Also by opening 1♣ we are least in the way of partner when we have hands that could play in at least 2 or 3 strains.
Let me notice some trends from one side to the other:
From English Acol to 2/1, the minimum strength of auctions like 1♥ - 2♦ increases. This is no doubt caused by the opening structure. The lack of definition for the 2/1s in English Acol is a big problem, but without them you have to respond 1NT to 1M too often. With them, slam bidding becomes much harder than in 2/1. Not my cup of tea (and tea is without milk!)
The opening bid of 1♦ makes a transformation from well-defined for Acol to vague and then back to well-defined. This is the main flaw of the systems in the middle, I think.
1♣ gets to include more and more hands from up to down. I think every step (except the first which is not helpful at all) is an improvement in this case as it helps define the other opening bids more than that it hurts 1♣.
Let's start on one end of the spectrum.
English Acol - 4444
All opening bids on the 1-level promise a minimum of 4 cards. With 4M + 4m usually open the major. There is some freedom here. This system has the advantages that 1M can preempt the opponents and that 1m are well defined, however the disadvantages are that 1m are less frequent and 1M have more bidding problems, esp. after interference.
Dutch Acol - 4444
In Dutch Acol you bid 4-card suits bottom up. This may seem silly and frankly, I think it is. The biggest problem is 1♠, which is either 4♠333 or 5 cards. You want to know which variation is the actual one, especially in competition! Although the string of opening length did not change this is in fact the biggest step between systems! All the others just revolve around one or two distributions.
Swiss Acol - 5443
This is like Dutch Acol but 4M333 hands are opened 1♣. You have the advantage of 1♠ showing 5 cards but not for 1♥, which may have 4 cards if it also has 4 cards in ♠. This makes it harder to find fits in ♥ as partners have no certainty.
SEF, SAYC, 2/1 - 5533
This is like Swiss Acol only the 4♠4♥32 hands are opened with the 3-card minor. Now 1♥ promises 5 cards, making life easier for responder. This means that 1♦ is only 3 cards if 4♠4♥3♦2♣. This gives the same problems as 1♠ in Dutch Acol and 1♥ in Swiss Acol, we keep moving the problem down. Here it is again:
1♦ (2♥) ?
You have 4♦ 2♥ and want to find a bid. Your length in ♦ increases the chance that partner is short, and if he is you know that he has 4♥. So either we have a 4 - 4 fit and they probably have a fit somewhere too, OR we have only 7 cards in ♦ and the same is true for their ♥. Your guess!
Italian 2/1 - 5542
This is like SEF but hands with 4♠4♥3♦2♣ are opened with 1♣. I prefer this method by far over any of the above. Note that we have moved our problem down another step now. However, it is best faced in 1♣, the most shaded of the opening bids even before this problem. Also by opening 1♣ we are least in the way of partner when we have hands that could play in at least 2 or 3 strains.
Let me notice some trends from one side to the other:
From English Acol to 2/1, the minimum strength of auctions like 1♥ - 2♦ increases. This is no doubt caused by the opening structure. The lack of definition for the 2/1s in English Acol is a big problem, but without them you have to respond 1NT to 1M too often. With them, slam bidding becomes much harder than in 2/1. Not my cup of tea (and tea is without milk!)
The opening bid of 1♦ makes a transformation from well-defined for Acol to vague and then back to well-defined. This is the main flaw of the systems in the middle, I think.
1♣ gets to include more and more hands from up to down. I think every step (except the first which is not helpful at all) is an improvement in this case as it helps define the other opening bids more than that it hurts 1♣.
