[Jinksy]

Please construct a pair of hands (ideally several) that a sensible 2/1 GF sequence gets you to a contract that a sensible 2/1 NGF sequence will likely miss.

I'm sure there are plenty of such hands, but I still haven't got a sense of their qualities to know what I'm gaining in return for what seem to me to be the more obvious losses (when 1N is the only making contract, for eg).

Still thinking of having NGF 2/1s in Fantunes. It seems like without them you're making life deeply unpleasant for yourself when (for eg) you have a balanced 21-24 count with a 5cM, and after a Gazzilli sequence, p shows you a min, esp if his rebid is 2N or above.

[aguahombre]

I know this is not exactly responsive to your request for specific hands, but the hands we have played over the years and were delighted that the G.F. aspect was resolved early sort of all run together in my mind.

However, they do seem to fall into categories:

--4th hand starts interference and we know we are committed to game-level or penalty.
--unnecessary jumps can be quite limited and descriptive.
--we can support the 2/1 suit immediately and then slowly probe for alternate strains.

Those who play NGF can do these things, also, with different follow-ups, but we like the extra useful space and the fewer possibilities mixed into 4th suit bids and cuebids.

BTW, why do you need to be convinced about one or the other?
Pick one with your partner (u seem to lean toward non). Use it for several months and a lot of hands, then decide if you are content or if you come up with enough situations yourself which will change your mind. Everyone here will be prejudiced one way or another (including me), and will find arguments which support their style. Books, also, reflect the agenda of the authors and tend not to give the negative side of what they are promoting.

This post has been edited by aguahombre: 2011-December-02, 09:32

[Jinksy]

In response to your question, I and a few regular Ps are trying to settle on a coherent (Fantunes derived) system that doesn't have anything that we consider glaring flaws. I'm actually slightly in favour of 2/1 GF, but it makes life extremely difficult after a 1N response when the range on it is 0-8!

[aguahombre]

Sorry, I don't think my post has much to offer when the question is about 2/1 G.F. with a 0-8 NT response.

There are some things which go together when you play 2/1, and some which are very hard to reconcile when you do.

[awm]

Here's one Sam and I had at nationals (spots approximate):

---

South bid 3♠ at second turn because 2♠ would've been non-forcing in our methods. The 4♦ cue shows extras and denies a club control (we play non-serious 3NT); however this is in the context of a strong club system with light openings, so a lot of 13-15 counts qualify. The 4♥ bid showed a club control and further interest, 4♠ was not forcing, and south continued cuebidding to drive to slam. Perhaps one or both of us could've done more, since a very good grand was missed, but they both seem like judgment calls (should north cue again despite lacking any outside first round control and having already made a "serious" try? should south look for grand even though north couldn't move over 4♥?).

However, note how easy this would be if we played 2/1 GF. Our auction would start:

1♠ - 2♣
2♥ - 2♠
3♠...

Where the 2♠ call is GF and the 3♠ call shows the sixth spade. South can now visualize that we have no minor suit losers, and the trump suit is no longer a big concern since we have a known ninth spade. He can pretty much keycard at this point, or cue a couple more times first (it doesn't really matter); it will be easy to reach grand. On our actual auction the ninth trump never got shown, because we had to jump to 3♠ in order to force!

[EricK]

It may not be exactly the sort of thing you are looking for, but responder having a weak hand with a 6/7 card suit and opener having a minimum balanced hand with a 5 card major.

eg 1♠ 1NT 2♣ 2♥ vs 1♠ 1NT P

Other examples could depend on exactly what agreements you have about how far you are forced following a 2/1 (which is itself one of the advantages of having a very clear definition such as 2/1 GF!). eg After 1♠ 2♣ in 2/1 GF opener has the option of supporting ♣ immediately, or temporizing and supporting ♣ on the next round. With probably the former showing extras and at least some interest in a ♣ slam. You might lose this ability if opener isn't guaranteed another chance - or if an immediate 3♣ rebid by opener was passable.

[han]

Given a sensible system, it is very hard to construct a pair of hands where you can't bid to the optimal spot seeing both hands. Adam's hand above is a good example where 2/1 makes it easier to bid the grand. But Jinsky, if you are stubborn and you want to convince yourself that your sensible NF2/1 system is better, it should be easy to find a sequence in your system where you would do just as well.

It is usually really hard to determine whether one system is better than the other. However, it should not be so hard to see the advantages of one system over the other, hand types where one system will have an easier time than the other. In 2/1, if the auction starts 1S - 2D, you tend to be ahead of the pairs that do not play 1S - 2D as GF. Simple because the 2D bid contains fewer hand types you will sometimes have an easier time bidding to the best spot. That doesn't mean that the other pairs won't be able to bid to the same spot. But often they will have to guess, and those guesses can be easier when 2D is more narrowly defined.

My apologies for stating so many obvious things.

[kenrexford]

There are any number of very case-specific holdings where you are better off, IMO, with a 2/1 GF system on those hands. These will typically be ones where specific cards must be shown to reach rather light slams.

And example might be AQxxx-xxxx-KQ-xx opposite Kxx-Ax-AJxxx-Axx. 12 tricks are there with normal splits. But, you need the ability to show specific cards and the space to do it.

With 2/1 GF (at least my way):

1♠-2♦
2♥-2♠(sets trumps)
3♦(two top spades, no club control, one of top three diamonds)-3♥(one of top three hearts)
4♦(not three top spades, non-serious, second top diamond)-6♠ (or something slower to find out if maybe a grand is on)

With Non-GF, I wuld imagine an inability to find out all that needs to be found out in time. Of course, maybe NGF has methods as advanced as what 2/1 GF sometimes has, in which case I could be wildly off base.

[aguahombre]

 kenrexford, on 2011-December-03, 11:30, said:

Of course, maybe NGF has methods as advanced as what 2/1 GF sometimes has, in which case I could be wildly off base.

I am sure the experienced and/or top flight pairs do have quite advanced methods. But they first have to wade through the nebulous parts of the early auction to get to the starting point of slam exploration.

Vugraph often reveals these auctions where they take a few more rounds of bidding to arrive where you or I might get in the first two or three exchanges.

And they seem to have a few more accidents along the way.

This post has been edited by aguahombre: 2011-December-03, 11:49

[Cascade]

 awm, on 2011-December-02, 21:41, said:

Here's one Sam and I had at nationals (spots approximate):

---

I am not sure about the mid auction especially between 3♠ and 4♠. However in the late auction north needs to get to a position where he can bid Blackwood. He has a hand that just needs specific key-cards and can easily bid the grand if partner shows three key cards, the ♠Q and a minor suit king.

Since 2♥ is already very wide ranging I am not sure that my partner or I would show extras. Bidding a frivolous 3NT to show a minimum 11-14 or so albeit good within that range and then bidding Blackwood when partner shows extras will easily get you to the Grand.

[han]

Ha, Cascade proving my point!

[awm]

Indeed, it's hard to give a hand where it's impossible to bid a slam without playing 2/1. That's not the point.

Nonetheless, a fairly good and established pair missed the grand slam on this hand. While there were some questionable calls (as usual when a less-than-best contract is reached) I don't think anyone did anything obviously wrong. A hand where grand slam should be almost automatic playing 2/1 GF became a hand with a sequence of close judgment calls that we evidently got wrong. Sure, we could've gotten these judgment calls right. We might even get them right a majority of the time. But we obviously don't always get them right. Playing 2/1 would've saved us a whole level of bidding on this hand and would make it pretty easy.

With that said, there are reasons we don't play 2/1 GF, and we don't plan to switch.

[Cascade]

 han, on 2011-December-03, 16:28, said:

Ha, Cascade proving my point!

I am not sure that one example proves your point.

In general slam bidding should be easier than game or partscore bidding as we have more bidding space to investigate.

In your example after

1♠ 2♦ if you have a game hand you are better off as 2♦ is more limited than in a one round force system.

Ironically on the same auction while with 13 hcp the non-2/1 players are worse off when they have a little less but still a 2♦ response they maybe better off since

1♠ 2♦ delivers more information than 1♠ 1NT (assuming the hand is not suitable for 1♠ 3♦) although it costs a couple of steps of bidding room.

However there is more to it than that. In some auctions after the good start (for 2/1) 1♠ 2♦ the 2/1 players give back some of their advantage by making certain rebids more frequent and thus include less information e.g.

1♠ 2♦
2♠ - wide ranging

So opener has more information but responder has less information compared with the identical auction with identical hands but the response was not Game Forcing.

Continuing the auction further the 2/1 GF responder maybe now able to preserve some bidding space thus gaining back some of the lost advantage from the rebid.

1♠ 2♦
2♠ 2NT forcing

compared with perhaps

1♠ 2♦
2♠ 3NT - loss of bidding space in the non-GF 2/1.

Obviously this sort of analysis does not have a simple answer. In the end we have the same number of bids to convey information. Different methods will have advantages and disadvantages but if they are reasonably well designed I suspect they will deliver similar results. I suspect the differences will be least at the slam level since there is more space to exchange information.

[han]

 Cascade, on 2011-December-03, 18:54, said:

I am not sure that one example proves your point.

I think you didn't read my point.

[benlessard]

In modern 2/1 except if suit repeated, the painful cases are 1S--2D--2S where you have a good hand with nothing in H for example, bidding 2Nt catch all might wrongside the contract, 3D isnt forcing and 3C might get raised to 4C (one way to deal with is using transfers rebids or switching minors, it allow you to still stop at 3D while being to have a catch all bid.)

In old style standard AM you often lose a full level since raising isnt forcing (2nt is also NF) the ability to bid 2/1 with a bad suit and 10-11 pts inst worth the high cost of not being able to GF cheaply in many auctions.

Ive have a strong preference for 2/1 except if suit is repeated, it allow you to play 1nt semi-forcing (6-11) and have all the benefits of 2/1 except some minor exceptions the drawbacks are a 2/1 has to show GF values or a very good suits (wich in term of frequency is very close to 2/1 100% GF) and taht your 1nt is now 6-11 and not 6-9.

[Vampyr]

I don't play 2/1 GF, and don't play against it enough to know whether there are problems in competitive auctions when the 1NT response can show an invitational 1-suited hand; but it seems likely that 2/1 GF can be useful for games and slams but loses in battling for the partscore.

I think that improvements can be gained if 1M-2m is GF and 1♦-2♣ and 1♠-2♥ are not. I don't know how popular this method is or whether it has proved helpful for those who do play it. I know a few pairs who play 1M-2♣ as artificial and GF, which is another way to try to have the best of both worlds.

[phil_20686]

I think that one should also take note of the degree to which being in a GF allows one to develop more sophisticated methods. A particularly glaring example is 1S-2H, where the ability to bid 2S as forcing with a 2N shape ask effectively gives opener twice as many sequences as are available when 2S is NF.

If all I did with these sequences was to take the Non GF continuations, and divide their ranges in half, I would still be well ahead on these auctions. In fact most of us has much more useful things to do with these sequences.

Of course, you are on a loser when partner has an invitational hand, but in reality, you often (maybe even normally) do not have the auction to yourselves in a part score battle. To give up definition on constructive auctions where a large fraction of the time the opponents are intervening anyway, in order to gain on hands where the opposition are reasonably unlikely to have the values to intervene, seems like a no brainer to me.

Of course, the lower level bridge you play, the less likely opponents are to intervene, and the more gain there is in having extra invitational sequences.

[kenrexford]

The way in which non-GF would in a theoretical discussion possibly have an edge over 2/1 GF would be in that sliver of hands appropriate for a 2/1 non-GF stuck into 2/1 GF's 1NT.

However, how great are these auctions?

I mean, playing Standard, you hear 1♠ and are able to bid 2♣ with a 10-count. You still haven't promised clubs, so partner does whatever he does. If you want to show real clubs, you have to bid 3♣.

In 2/1 GF, using intermediate jumps, you bid 3♣ immediately. or, partner bids clubs because he is forced to bid something.

My point is that the mere fact that you can mention clubs yourself with the tweener hands does not necessarily improve the partscore situation. It just means a different route with these hands a lot. A different route is not by being different superior or inferior.

In fact, one might argue that 2/1, when in the tweener zone, might gain in that one hand -- Opener's hand -- is typically developed really well, making Responder a knowledgable captain, whereas with non-GF, both sides are explaining less of their hand without captaincy known, which gets messy.

There are auctions where non-GF works well, but some of these could be better handled if 2/1GF folks added a gadget or two. One example is the handling against Lall of a Responder's hand with five hearts and tweener after a 1♠ opening. Ditching 2NT jacoby to allow 2♥ or 2NT either one with five hearts, one tweener, a thing I have used before, solves that specific problem well.

[Cascade]

 han, on 2011-December-03, 16:28, said:

Ha, Cascade proving my point!

Oh I thought you meant your point was:

 han, on 2011-December-03, 06:07, said:

Given a sensible system, it is very hard to construct a pair of hands where you can't bid to the optimal spot seeing both hands.

but you also made a comment about the specific hand.

Quote

Adam's hand above is a good example where 2/1 makes it easier to bid the grand. But Jinsky, if you are stubborn and you want to convince yourself that your sensible NF2/1 system is better, it should be easy to find a sequence in your system where you would do just as well.

But the original question was more in line with your general comment not the specific one about that his hand.

Quote

Please construct a pair of hands (ideally several) that a sensible 2/1 GF sequence gets you to a contract that a sensible 2/1 NGF sequence will likely miss.

[Vampyr]

 kenrexford, on 2011-December-04, 11:18, said:

I mean, playing Standard, you hear 1♠ and are able to bid 2♣ with a 10-count. You still haven't promised clubs,

?