BBO Discussion Forums: ACBL Legal MOSCITO - BBO Discussion Forums

straube, on 2010-December-27, 00:36, said:

Misapplying.

There is a provision that methods authorized under that provision need an approved written defense.

straube, on 2010-December-27, 00:36, said:

Yes, the Midchart used to be quite permissive in allowing artificial suit-showing openings under the "4 card known suit" clause. That was found to allow Moscito, and hence the new Midchart removed this and replaced many of the "general" rules with very specific "allow" clauses that can't accidentally allow other interesting systems to arise. In fact, the only 1 level bids allowed by MC not allowed under GCC are playing 1M as strong (15+) and artificial, for both people who want to play a strong 1H system. There is still a provision for 1H showing spades under MC, but I believe they revoked the approved defense for that, rendering it legal but unplayable. They also recently banned 2 suited 2 level bids that might only have 4-4 shape, something that was previously possible at least some of the time.

It's a sad day for creative minds in the US when more things are allowed in a New Zealand club game than are permitted in the NABC+ top tier SuperChart events in the US. You know, because Meckwell & Co. need to ask for your defense against multi (just in case you forgot to bring it), but they can't possibly beat you playing forcing pass.

straube, on 2010-December-27, 00:36, said:

It's pretty much unplayable.

Especially the 1♠ opening showing 4+♦ needs a non-GF 1NT relay. On the other hand, is it really a relay, or is it similar to a forcing 1NT in 2/1? Where is the difference explained?

The 1♦ and 1♥ openings may be playable, but you get into trouble with invitational hands. You lose a lot of space. These days, the relay includes a simple 1NT response, a balanced invite, an invite with support, or any GF hand. Playing the relay as GF only removes an aweful lot of hands from that relay, which also removes the possibility to play 1NT and 2m as transfer responses (which are also used for constructive purposes). So bye bye constructive raise, bye bye 6-11 transfer responses,... There's almost nothing left of the good stuff.

Free, on 2010-December-27, 02:05, said:

I think that the regs say you can't have a relay that promises GI+ values. It has to promise GF values or less than GI values. So for example, it would be legal to play 1S-1N as 0+ (a la Fantunes) or 1S-1N as GF but not 1S-1N as something like 10+.

If 1D and 1H were legal openings, one would probably have to choose 1H and 1S responses as constructive/GI forces and move the GF relay to the second step.

straube, on 2010-December-27, 08:59, said:

Under responses and rebids, the The GCC explictly allows

Quote

I wouldn't be surprised to discover that the regulators assume that said 1 Major open is natural, however, that's not the way they chose to write the regulation.

Regardless, the point is moot since

1. There is no approved defense to a 1♠ opening that shows a unbalanced hand with 4+ Diamonds
2. The Conventions Committee has made it pretty clear that there will never be an approved defense to a 1♠ opening that shows an unbalanced hand with 4+ Diamonds

awm, on 2010-December-25, 01:18, said:

We tried a 2♠ opening as 4♠ 5+♣ and it didn't work well (at least not in partnership bidding). We were getting burned at a pretty high rate for not being able to play 2 of opener's primary suit. However, since we removed the ♥-♣ hands to 1♥, might be able to try something like this:

1♣ = 15+ any
1♦ = 4+♦, not balanced, 10-14, denies 4-card ♥
1♥ = 4+♥ 10-14, may have minor-suit canapé
1♠ = 5+♠ 10-14
1NT = 11-14 balanced
2♣ = 6+♣ or 5+♣ 4+♠ (denies 4♦ or 4♥)
2♦ = weak 2 in a major
2♥ = majors weak
2♠ = any ♣ preempt, or a bad ♦ preempt
3♣ = minors weak
3♦ = sound preempt


So a 1♥ opening can have:
4+♥ 4+♣
4+♥ 4+♦
6+♥
5+♥ 4+♠
4♥(441)
44(50)
04(54)
5♥(440)

I think that's all of the hand types. However, on partscore hands, how would we find ♠ if we use 1♠ as the strong response? Might be better to use 1♠=forcing NT, 1NT=GFR, 2m=5(+)♠ better minor and 1♥-2♠ = natural weak? Then after 1♥-1NT, can maybe use something like this (and this is very much off of the top of my head)

2♣ = 5+♥ 4+♠ or 3-suited
---> 2♥ = 5+♥ 4+♠
......2♠ = 44(50) or 04(54)
......2NT = 4(441)
......3♣+ = 5(440)
2♦ = 4+♥ 4+♣
2♥ = 6+♥
2♠+ = 4+♥ 4+♦


And after 2♣-2♦:
2♥ = 1-suited
2♠ = 5♣ 4♠ (can only be 4(31)5 or 4225 since 4(40)5 opens 1R, now 3♦ = GFR, 2NT/3♣ = INV)
2NT = minimum 4♠ 6+♣, 0-1♥ or equal short
3♣ = minimum 4♠ 6+♣ 0-1♦
3♦ = maximum, 4♠ 6+♣ 0-1♥
3♥ = maximum, 5=1=1=6
3♠ = maximum 4=2=1=6
3NT = maximum 4=3=0=6
4♣ = maximum 5=2=0=6

(we've chosen to omit 7/4's when a 5/5 step is not available because 6-5 is statistically more common than 7-4 according to the Encyclopedia of Bridge)

Any thoughts on this structure?

Also, the ACBL has approved the defense to a 1♥ opening showing 12-21 pts and 5+♠ that uses totally natural responses, including a 1♠ response as a sign-off. Wonder why this was approved but we can't get something similar approved for 1♦ opening showing ♠ which is probably easier to defend against because the opponents have an extra call below 1♠ that isn't afforded by the 1♥ opening showing spades.

I'd love to see the frequency distribution for your openings. If you have the time, please post it.

I think your 1H is very overloaded and your 1D is very underloaded. You almost need your 2D opening to show 5H/4D and your 2H opening to show 5H/4C to take the pressure off of your 1H.

LOL at 1H (showing spades) P 1S to play.

olien, on 2010-December-27, 09:41, said:

The 1♥ submission in question is an outlier:

Back in the day, when I was still fighting with the ACBL regarding suggested defenses to

1♦ = unbalanced with 4+ Hearts
1♥ = unbalanced with 4+ Spades

Tim Goodwin decided that it might be worthwhile to create some test cases and try to establish whether there was any kind of clear demarcation regarding what kind of transfer opening were/were not legal.

Tim submitted a 1H opening that was completly identical to a Standard American 1S opening along with a suggested defense. (Tim wanted to see whether the "majors first" /light opening style was the issue. As I recall, the submission was

1. Originally bounced because the suggested defense didn't describe the responses to the 1H opening.

2. Tim then added a response structure that included a natural, nonforicng 1♠ response. The suggested defense was then approved for some silly class of events (Team events with at least 12 boards)

3. The defense was later deapproved

The whole situation was as idiotic as any other exchange with the Yahoos on the Convention Committee.

From my perspective, the most interesting part of the exchange was the claims by the Convention Committee the adequancy of the defenses depended on issues like the frequency of the opening bid and the response structure of the opening bid (It became blatantly obvious that the Defnese approval process had little to do with the actual defenses in question and an awful lot to do with ways to eliminate opening bids that they didn't like)

olien, on 2010-December-27, 09:41, said:

When I submitted a 1♦ transfer opening (otherwise identical to the already approved 1♥ transfer opening) the C&C Committee reconsidered and removed the 1♥ transfer opening. I say "removed" but last I checked the defense was still in the defense database. I think it was summer 2009 that the method was supposed to have been removed from the defense database so it has been a while. I sent a reminder about this (probably more than one) to the committee chair and someone at ACBL, when nothing happened, I wrote a letter to the (then) President of the ACBL pointing out that there was a problem in the process. Still nothing.

At the time of approval, the sticking point with the committee was that the transfer opening had to be forcing. They did make me run through hoops by specifying a complete response structure and outlining all possible defensive actions -- it was not enough to say "treat the opening like a standard 1♠ opening except..." and mention the very few exceptions, nor was it enough to say "jump overcalls are xyz". It made what could have been a very short defense run to three pages (as I recall). One thing I wondered was if I had decided I wanted to play 1H-3S as limit instead of weak, would I have had to submit a whole new method and defense for approval.

The committee did express some curiosity about what I would do with a 1♠ opening. I was upfront about not having complete system worked out, but described some GCC legal options for 1♠. The committee recognized they were not charged with system approval but rather convention approval and did not push this during the approval process.

That explains the 1H-1S (to play) submission. I wonder if he tried 1H-1S (showing hearts). Now the defense is in the same position after 1H-1S natural except for where the hearts and spades are located. Agree it sounds like they just wanted to kill 1H showing spades.

straube, on 2010-December-27, 11:15, said:

I did not try any other meaning if 1♥-1♠. I wanted to parallel standard bidding as much as possible. Removing the hands that would pass a standard 1♠ opening from the 1♥-1♠ sequence would have meant changing some otherwise standard response (to accommodate weak hands) and I did not want to do that.

So, after a tournament of trying this, we've decided the 2♣ opening needs better definition. We didn't like the potential for a 5-card suit in the 2♣ opening. So, we've gone with part of Larry's solution, and are now using the following opening structure:

1♦ = 4+♦ 10-14 HCP, may be ♣ canapé
1♥ = 4+♥ 10-14, may be 4414 or 4405 or 4♥-5♣
1♠ = 4+♠ 10-14, may be ♣ canapé
1NT = 12-14 balanced
2♣ = 6+♣ 10-14, <4♦ <4♠
2♦ = weak 2 in either major
2♥ = weak both majors
2♠ = 5+♠ 4♣ 10-14
2NT = any ♣ preempt or bad ♦ preempt
3♣ = both minors weak

Thoughts?

Perhaps some four-card major fans can correct me on this...

Suppose you are playing a four-card major (possibly canape) system whereas your opponents at the other table play five-card majors (with the same approximate point range).

I'd expect that you tend to lose on hands where you actually have a five-card major, because your opponents have more information and can better judge how high to compete, what to lead on defense, and so forth.

I'd expect that you tend to win on hands where you open a four-card major, because you can sometimes find a major fit that's hard to discover otherwise, have a quicker auction that leaves opponents in the dark, and so forth. I'd also expect you to win somewhat on hands where you open in a minor, because you can forgo looking for 4-4 major suit fits.

The problem with this structure (and many of the structures proposed in this thread) is that you seem to have the disadvantage of four-card majors while misplacing a number of the advantages. Here, 1♥ only guarantees four hearts (causing losses when you actually have five)... but hands with four hearts and longer diamonds are opening 1♦. Even hands with 4♥ and 6♣ are opening 2♣, so you have to look for 4-4 heart fits over that opening too. So it seems like you're trying to minimize your hands where you open 1♥ on four, while still opening 1♥ on four frequently enough that it doesn't guarantee five. That seems like a losing strategy.

awm, on 2011-January-11, 15:51, said:

I think that's right and had written along those lines...

Quote

I'm still wanting them to post the frequency distribution for openings.

@olien, I'm not in America so am not sure of the MC regulations but one solution to your problem might be to invert the 1H and 1NT responses to 1D and move all of the problem hands to the 1D opening. This will naturally draw even more derision from the crowd since it is yet another step towards a more Precision-like system. There would still be some issues to sort out but it is one additional option that I did not see mentioned earlier.

awm, on 2011-January-11, 15:51, said:

Hi Adam

There are some additional considerations that need to be factored in to the equation.

Assume for the moment, that a 5 card major player opens 1♠ and the auction starts

1♠ - (P) - 2♠

Assuming that the 5 card major player is using a normal response structure, the opponents know with certainty that the 5 card major opener is resting in an eight+ card fit. In turn, the opponents are relatively well positioned to apply the Law of Total Tricks and make a decision whether to balance or pre-balance.

Now, assume that a MOSCITO player opens 1♥ (showing 4+ spades) and the auction starts

1♥ - (P) - 2♠

In this case, the only thing that the opponents know with certainty is that the 2♠ bidder normally holds exactly three card support. Its unclear whether the opponents are sitting in an eight+ card fit (in which case balancing is pretty important) or a 7 card fit, in which case balancing can easily lead to a poor score. (The way things work out, the MOSCITO partnership will be resting in an 8+ card fit about 52% of the time and a 7 card fit ~48% of the time).

Moreover, the player who opened 1♥ knows

1. His own trump length
2. Partner's trump length (The 2♠ raise promises three card support)

He's in a very good position to make a well informed decision.

There's always an issue of strategy.

In Hrothgar's example, let's assume the opponents bid the same way they would over a raise in a 5-card major system. If opener actually has a five-card major, opponents will do just as well as before. If opener has only a four card major then it's possible you win the board.

Similarly, you could change your strategy opposite partner's four-card major opening and just always assume he has five. Then you will push the boards when he has five, but you are losing when he has four because you over-compete, don't look for side suit fits in preference to a 4-3, etc.

I do think Hrothgar's style will overcompete some boards and reach some bad contracts. In particular you have to raise to the three-level on 4-4 fits (playing a level higher than the field), and you will play a lot of 4-3 fits at the two-level (which is fine when opener's 4cM is strong, but Moscito makes no such guarantee). The hypothesis that opponents will overcompete and get into trouble is certainly possible, but strong IMP opponents do sell to 2♠ fairly often anyway....

awm, on 2011-January-12, 12:01, said:

Comment 1:

There are definitely boards on which we end up at a higher level than the field.

In my experience, the gains from the hands where the opponents make a poor balancing decision (they fail to balance when they should or, alternatively, they end up going down in a nonsensical three level contract) more than make up for these.

awm, on 2011-January-12, 12:01, said:

Won't it often be right to compete to the 3-level with a 4-4 fit? Especially when opener has a long side suit. There is also an advantage in getting to the three level before the opponents have had a chance to get into the auction -- 1M-3M is more effective in keeping the opponents out than 1m-1M-2M.

I don't know about playing a level higher than the field, because the field will seldom let us play at the two-level in a known eight card fit. Sure it will happen sometimes, but I don't think it will happen a lot.

hrothgar, on 2011-January-12, 09:15, said:

I've never been comfortable with that style, whereby a single raise of a likely 4-card major denies 4 trumps. In the early days of Moscito, this was making a necessity of convention.
In 1985, 1♠ showed 4+♠s and denied 4♥s. In response, 1NT was 11+ relay.

Thus a responding hand like

♠Jxx ♥Qx ♦Axxx ♣Qxxx

raised to 2♠ quite happily, since 1NT was out and he knew the opponents had 8+♥s. In those days 1♥ & 1♠ were 4-card suits 53% of the time. That example was clear enough but Paul Marston also did it on less suitable hands, reaping a benefit when the opponents stepped in, and also when they were afraid to ...
However, auto 3-card raises rate to lose long term in a 2-handed game and opponents are starting to judge these auctions better.

Whatever the reason, Marston started to move some of the 4-carders out of 1M. These days, 11-12 flat opens 1NT, 4-6 hands with long minor show the minor first & there is no denied major. (4-5 hands show long hearts, 5-4 hands show long spades)
With these changes, the chance of 1♥ (=♠s) being a 4-carder are around 40%.

That makes a 3-card raise more attractive. Certainly taking out 11-12 flat avoids some silly -300s. However, it still feels wrong at times to routinely bid beyond the TNT. 4333s with 4 trumps should pretend they have 3. I also tend to stay low on hands with 4+ in the other major. So

♠Qxx ♥KTxx ♦Qx ♣JTxx

feels like a 1NT response to 1♥ (=♠s) (Or in our case, 1♦ = ♠s, not ♥s)

Of course you don't want to stretch this too far. If a raise shows 3 or 4, neither will be able to diagnose a 9-card fit and push to the 3-level. I like a bit of flexibility. For us, a jump major raise shows a shapely raise to 2M. That's any hand with 5 trumps, or 4 chunky ones, or 4 and a bit of shape. (That might simply mean a doubleton in opener's denied major. Yes, we still play that way)

It's true that Standard & Precision have an advantage whenever they have a 5-3 major fit but the gain is small. With methods that open 4-card majors, the gain is in finding the 4-4 fit faster, hitting the 3-level quickly with the 4-5 fit, plus messing with the opponents' TNT assumptions.