TomReynold

True. I play 1D=15+ 1D-1H (6-9 or 14-15), 1D-1S (0-5) and 1D-1NT and above Symmetric Relay. The system is GCC under the old method and the only pre-alert is the canapé 1H and 1S opening which is not necessary to play.

We looked at a Polish Club with a medium NT (13-15HCP) but the problem is that statistically a 1C opener is the weak hand and the system resolves to the nebulous diamond (now nebulous club) on steroids. In our current system we open a 4 card major with 14-16. This works well in competition because in competition, when responder supports on 3 card support and 10HCP, opener has the power to bid 3NT with a 4 card major or play game on the 4-3. However, with a weaker opening the 4 card major doesn't work very well. To flip-flop our NT range Vul vs NV we went to a Meckwell type approach.

Thanks Mike.

I noticed that according to one write up on the Meckwell System that they paly transfer responses after 1D/H/S-X. That makes sense but does anyone know if it is legal per the ACBL? Thanks, Tom

Over 1C-1D (natural) I chose to keep the Mavarako structure which is transfer 1H and 1S bids. Pass is weak. Double is takeout inviting opener to bid 1NT. Our experience is that when responder makes a semi-positive response, a possible slam is in the cards if the club opener is large. Mavarako opens 1C with hands other systems may open with 2NT.

This is a RFC (Request for Comment) on a system for combating interference over a big Club 16+HCP. Comments and suggestions for improvements are solicited. I understand that the formatting lost while posting her makes following the logic difficult. If you would like a copy in word or pdf format please email tomreynolds_ilan@yahoo.com or send me a message here. Mavarako System Competition over a Forcing Club Theory of Operation In the mini Spingold 2015 most pairs played either nothing or Mathe. (Double for Majors, 1NT for the minors.) Via a simple overcall, the goal of the opponents is to disrupt the club system sequence and, if a fit is found preempt to the appropriate level. Further, if responder becomes declarer, the opening leader can lead through the club openers hand, hopefully finessing the club opener on the opening lead. The Mavarako system seeks to negate those goals. Most modern Club systems play transfer responses, at least in the majors. A few show controls. However, once the opponents intervene I submit transfer responses are indicated as opposed to controls. The danger of preemption is simply too great. Most systems employ a card showing double by responder (1C-1H-X) of an intermediate strength (5-9HCP) to show opener that responder has some values. After interference over 1C, Mavarako also uses a card showing double but only with a balanced hand. This modification tells the club opener that in addition to some values, opener can expect some support in responders hand. In addition, the last thing Mavarako wants the opponents to do is lead the overcalled suit THROUGH the club opener. Therefore, Mavarako plays four suit transfers by responder. The level of transfer indicates the length of the suit responder is transferring. 1C-1D (overcall)-1H shows responder has 4+ Spades, 1C-1D (overcall)-2H shows responder has 5+ spades. Opener need not accept the transfer if he is unbalanced. Although designed for Mavarako, the system for handling competition over a forcing club is also applicable for most systems employing a forcing club such as Precision, Neapolitan or Blue Team. However the HCP ranges may need to be adjusted. Mavarako System The Mavarako System employs a forcing club that is 16+HCP for any hand that can rebid 1H, 1S or 1NT, 17+HCP for hands that rebid clubs and 18+HCP for a hand that will rebid 2D. Responses are: 1D 0-6(7) or 11+HCP 1H 7-11 showing 4 Spades 1S 7-11 showing 4 Hearts 1NT 8-10 Natural 2C, 2D 7-10 Natural, no 4 card major 2H-2S 8-11 Smolen type (5-4) major two suiters 2NT 12+HCP Natural 3C and above transfers showing a 0-1 loser suit and at least 1 Ace Bids marked no change are following this structure. Precision Systems Precision Systems using a 16+ HCP Club should adopt the Mavarako ranges. Precision Systems showing 17+HCP unbalanced or 18+HCP balanced should drop the response HCP range 1HCP Neapolitan System Neapolitan and Blue Team systems showing 17+HCP balanced should drop the response HCP range 1 HCP General Rules One level Interference 1. 1NT is natural 2. All suits are transfers except 2C/1D 3. 2S is an artificial game force 4. 2NT and above no change 5. Excluded Transfer is a club transfer or Stayman 6. Double is card showing Two level Interference 1. 2S is an artificial Game force except for the flip-flop over 2D 2. Excluded Transfer is Stayman a. If the excluded transfer is 3NT or 3C, it is puppet Stayman 3. 2NT is a Club transfer 4. X is a negative double Three Level Interference 1. After 3D transfers stop 2. 4 Clubs is a major two suiter Single suit (Natural) on the one level One level bids of 1S or less typically do not, by themselves, disturb the Club auctions. The major suit transfers and responses remain. This is by design. Mavarakos goal is that a cheap overcall by opponents should not disturb Mavarakos carefully coded responses. In contrast, the overcall should help. If the overcall is a single suit transfer, responder should bid as if opponents real suit was bid. Responders bids marked (No Change) means opener should respond as if the interference didnt happen. The danger is that overcallers partner may have a fit and attempt to jam the auction. Thus there are additional transfers on the two level to allow the partnership to find their fit and play from the strong side. Over intervention and a raise Mavarakos coded sequences are disturbed. However, the tradeoff is the information gained. General rules With 0-6 HCP responder passes. 4 Suit transfers. Double is takeout and should not be passed If opener refuses a transfer and bids diamonds (potentially artificial) he is showing a big hand Over 1C-1D-? X takeout. Invites opener to bid 1NT with a balanced hand. 1H transfer with 4+ Spades, semi-positive minimum (No Change) 1S transfer with 4+ Hearts, semi-positive minimum (No Change) 1NT-no change 2C Natural 5 card suit 2D transfer to Hearts , 5 Card suit 2H transfer to Spades, 5 card suit. 2S artificial game force 2NT 12+ (No Change) 3C and above are transfers (No Change) Over 1C-1H-? (Or 1C-1D showing hearts.) X transfer to 1S. Essentially the same as bidding 1H (Transfer) (No Change) 1S denies 4 Spades. Potentially a club transfer. 1NT Natural (No Change) 2C Transfer to Diamonds (1C-1H-2C ♦-P-2H (Shows Spades) 2D (excluded transfer = Stayman), 2H Transfer to Spades, 5 card suit 2S artificial game force 2NT and above no change Over 1C-1S X Negative Double (shows 4 Hearts) 1NT Natural 2C Diamond Transfer [1C-1S-2C(Diamond transfer)-P-2D-P-2S (shows 4 Hearts +5 Diamonds)] 2D Heart Transfer 2H Club Transfer [1C-1S-2H (Club transfer)-2NT/3C- 3S (Shows 4 Hearts +5 diamonds) 2S is an artificial game force 2NT and above no change Single suit (Natural) on the two level With 0-6 responder passes. X is takeout but may be passed 3C is Puppet Stayman over 1C-2C and 1C-2D, Excluded Transfer (3D) is Stayman over 2H 2 Spades is an artificial game force except for flip-flop over 2D 2 Suit bids over 1C-2H and 1C-2S If opener refuses a transfer and bids diamonds (potentially artificial) he is showing a strong hand Over 1C-2C Pass is 0-6 or a penalty X. Responder assumes that opener will reopen with 16+ and short Clubs. Over a reopening double responder bids 2D with weakness. This allows opener to bid 2H or 2S. X is takeout at least semi positive. 2D is a transfer to Hearts 2H is a transfer to Spades 2S artificial game force 2NT Puppet Stayman (excluded transfer) 3C Diamond Transfer 3D is a Heart Transfer (Longer Hearts) 3H is a Spade Transfer (Longer Spades) 3S shows club shortness 3NT to play 1C-2D x- semi-positive 2H is a Spade Transfer (5 Spades) 2S Is a Heart Transfer (5 Hearts) 2NT is Club Transfer. (If over the transfer responder bids anything but 3D he has a diamond stopper) 3C is Puppet Stayman 3D is a Heart Transfer (Longer Hearts) 3H is a Spade Transfer (Longer Spades) 3S shows Diamond shortness 3NT to play 1C-2H X semi-positive 2S artificial game force 2NT is Club Transfer 3C is a Diamond Transfer 3D excluded transfer is Stayman. 3H is a Spade Transfer 3S asks for a Heart Stopper 1C-2S X-is a takeout double that can be passed Over X 3H shows 5 hearts by opener Over X 2NT does not deny 4 Hearts (responder Bids 3S over 2NT to show 4 Hearts) 2NT transfer to clubs. Any other bid by responder other than 3D shows a stopper) 1C-2S-2NT (transfer to C)-P-3C accepts transfer-P-4D shows a diamond heart 2 suiter. 3C Transfer to Diamonds 3D Transfer to Hearts 3H Stayman or minor 2 suiter 3S asks for a Spade stopper 3N to play 4C 2 suiter Clubs and Hearts 4D 2 Suiter Diamonds and Hearts Single suit on the 3 level With 0-7 responder passes A pass says either responder has a penalty double or a weak hand. A double is semi-positive or better. A new suit is semi-positive or better 1C-3C X-Takeout double that can be passed A bid of 3D by opener is game forcing, potentially artificial, and does not deny a 4 card major. Responder bids the major he does not have. A bid of a major by opener shows 5 3D Transfer to Hearts 3H Transfer to Spades 3S Transfer to 4D (or 3NT) 3NT natural 4C major 2 Suiter 4D Transfer to Hearts 4H Transfer to Hearts 1C-3D X Takeout Double that can be passed 3H Transfer To Spades 3S Transfer To Hearts 3N Natural 4C Natural Clubs 4D Transfer to Hearts 4H Transfer to Spades 1C-3H X Takeout double that can be passed 3S natural 3NT natural 4C natural 4D natural 4H Transfer to Spades 1C-3S X takeout double that can be passed 3NT to play 4C Natural 4D Natural 4H Natural Two-Suit Competition A new suit is semi-positive or better. Over competition, it is important for the responder, with a semi-positive response, to get his suit in early. Partner may well have a 15-16NT. Therefore, responder bids a natural suit whenever possible to show 7+ HCP. Except for the natural NT response new suits are forcing. In the 2015 Chicago Nationals Mini-Spingold, either Mathe or Suction was played by the opponents Versus Suction Suction either is a transfer to the next suit or it shows the succeeding two suits: 1C-X shows Diamonds OR Hearts and Spades 1C-1D shows Hearts or Spades and Clubs 1C-1H shows Spades or Clubs and Diamonds 1C-1S shows Clubs or Diamonds and Hearts 1C-1N shows Clubs and Hearts 1C-2C shows Diamonds and Spades There are variations on this theme. However this scheme is easy to remember because the Suction bidder never has the suit he initially bids. Not understood, Suction is confusing. Once understood, however, Suction has the weakness that overcallers partner (advancer) does not know partners suit any more than opener or responder. This gives responder the opportunity to pass with a penalty double of overcallers transfer suit. [1C-X (showing diamonds)-P!-1D-P-P (showing diamonds)-X (penalty double Diamonds). It also means that, after passing, if responder transfers into the overcallers suit he shows a penalty double of the transfer suit [1C-X-P!-1D-P-1H (I have Hearts and Spades)-2C (transfer to Diamonds. I had a penalty double of Diamonds)] One Level 1C-X Showing Diamonds or Hearts and Spades XX semi positive showing clubs 1D takeout double of Diamonds (essentially the equivalent of 1C-1D(natural)-X (take out double) all other bids are the same as if overcaller overcalled 1D natural 1C-1D Showing Hearts or Spades and Clubs X semi positive showing Diamonds 1H Shows 4+ Spades 1S Shows 4+ Hearts (Overcaller may not have Hearts) all other bids are the same as if overcaller overcalled 1H 1C-1H Showing Spades or Clubs and Diamonds X Shows 4+ Spades 1S Shows 4+ Hearts all other bids are the same as if overcalled 1S Two Level Bidding over Suction becomes more difficult on the two level. The point to remember is that, in Suction, the first bid is always the suit the Suction bidder does not have. 1C-1S showing Clubs or Hearts and Diamonds. Pass Does not necessarily deny a good hand. Responder may want to punish overcaller. However opener should treat a pass as negative until shown otherwise. Pass, then double by responder is penalty. X balanced card showing double 1NT Natural w/Clubs 2C Transfer to diamonds 2D Transfer to Hearts 2H transfer to Spades, 5 card suit 2S artificial game force 1NT showing rounder suites Suits (Clubs and Hearts) X balanced card showing double 2C transfer to Diamonds 2D Stayman (Puppet) Opener bids 2H with 4 Spades, 2 Spades with 5 Spades, 2NT natural 2H Transfer to Spades 2S artificial game force 2NT natural 2C showing pointed Suits (Diamonds and Spades) X balanced card showing double 2D transfer to Hearts 2H Stayman (Puppet). Opener bids 3 H with 5, 2S with 4, 2NT natural 2S Artificial game force 2NT natural 3C natural Versus Mathe Over 1C-x showing the majors 1 Pass is negative 2 XX is a semi-positive Club response 3 1D is a semi-positive Diamond response 4 All other bids are unchanged Over 1NT showing minors 1 Pass is negative 2 X shows a desire to punish 3 2C is a Heart Transfer 4 2D is a Spade Transfer 5 2H/2S are unchanged (4-5 in the majors) 6 3C is puppet Stayman Versus Brozel: X and xx show semi positive response in the other suits Transfers at lowest possible level Openers bid of a major shows 5. Responder may re-ask with 4. Higher cue bid shows positive response 1. X Clubs and hearts a. XX semi-positive negative double diamonds and spades b. 1D natural semi-positive c. 1H Spades Transfer (4+ Spades) d. 1S Diamonds Transfer e. 1NT natural and semi-positive f. 2C positive response 11+ (puppet Stayman) g. 2H Spades Transfer 5+ 2. 1D diamonds and hearts a. X semi-positive clubs and spades b. 1H Spade Transfer (4+) c. 1S Club Transfer d. 1NT natural and semi-positive e. 2C, 3C natural semi-positive f. 2D positive response 11+ (puppet Stayman) (2H shows 4 Spades) g. 2H Spades Transfer (5+) 3. 1H hearts and spades a. X minors semi-positive b. 1S Diamond Transfer c. 1NT semi-positive natural d. 2C natural semi-positive e. 2D, 3C natural and semi-positive f. 2H positive response 11+ 4. 1S Spades and a minor a. X takeout hearts at least semi-positive b. 1NT natural and semi-positive c. 2C natural and semi-positive d. 2D Heart Transfer (5+) e. 2H Diamond Transfer f. 2s positive 11+ Versus Cappelletti 1. X One suited hand (equivalent to 2 Clubs over NT) a. XX semi positive Clubs b. 1D semi-positive Diamonds c. 1H, 1S, 1NT, 2H, 2S unchanged d. 2C, 2D positive Diamonds 2. 1 Diamond (Majors) a. X minors semi-positive b. 1S Diamond Transfer c. 1NT natural and semi-positive d. 2C Semi-positive Clubs e. 2D Positive Clubs 11+ f. 3C natural and semi-positive g. 2H positive Diamonds 11+ 3. 1H Hearts and a minor a. X card showing double b. 1S Diamond Transfer semi-positive c. 1NT natural and semi-positive d. 2C semi-positive Clubs e. 2D Positive 11+ Clubs f. 2H Spade Transfer g. 2S Positive 11+ Diamonds h. 3C natural semi-positive 4. 1S Spades and a minor a. X card showing double b. 1NT natural and semi-positive c. 2C Semi-positive Clubs d. 2D Heart Transfer e. 2H Diamond Transfer f. 2s positive Club Opener rebids after interference General rule is that the first available pass by a Club opener denies 17+HCP. In a live auction: A double by club opener confirms 16+HCP and is for takeout A voluntary Club bid by the club opener confirms Clubs and 17+ in clubs A Major suit bid by club opener is 16+ unbalanced 2D is 18+ If responder has passed he responds as if the auction went 1C-1D-2D In a non-live auction: 1NT , a raise of a semi-positive response show the 16-17HCP range Major suit shows 16+, Clubs 17+, Diamonds 18+ A simple response to a cue-bid may be 16-17HCP or better As one can easily see, interference at a low level essentially helps the club opener partnership if the club opener is unbalanced.  

Vul against NV a double is for the lead. NV versus Vul a double or a bid suggests a sacrifice. I do not bid 4H.

In Mavarako, 1H/1S over 1D allow partner to pass with 0-3HCP. Over 1H, 1S is flip flop (forcing nt) and 1NT is 5 Spades. (With 4-4, opener bids 1S over 1D. The forcing Spade/forcing NT suggest no fit and some points 3-6. New suits are not forcing. (Except in the case of Mavarako 2D shows a positive response). In Mvarako over 1C/1D, 2D is a forcing trigger 20+HCP. A semi-positive response is 7-10HCP. I can post the Mavarako structure if you wish.

Using Neapolitan cue bidding works well with natural systems. The old rules are in the old book by Charles Goren. Interestingly the copyright is owned by Harold Ogust who probably wrote the book. Later Blue Team books have relaxed these rules somewhat. The original Neapolitan notes are on the internet. They don't go into the detail that the Goren/Ogust book does. Using Neapolitan D-I with the original rules is somewhat superior to RCKB. (I have not read Ken's book) D-I shows no 2 quick losers in your suits or the unbid suits and asks for NEW information. The auctions can get quite complicated. I have played D-I with my current partner for 40 Years. However, playing Neapolitan cue bidding with another partner, we used standard RCKB (1430) except for clubs (0314. It was acceptable. It is somewhat redundant as Ken says. My experience is that using D-I gets you to more good slams than RCKB, both using Neapolitan cub bidding structure, but also gets you to 50-50 slams(on a finesse)that you would stay out of using RCKC. If the opponents are expected to always get to the 5 level, 50-50 slams are actually odds on because they often go off in 5 with the right lead and the finesse off and they often make even if the finesse is off with the wrong lead. . However, this is an extremely aggressive approach that many partnerships don't favor. Tom

Actually, Not true. The original Neapolitan D-I works just fine. D-I by opener or responder with all positive bidding tempos shows 2 Aces. Responder responds with 1 Ace. Key Card works if you want to keep it simple.

Mistype. Staying up too late to watch the BB. Opener's 2H rebid confirms 5 hearts and 13HCP or less. 1H-2C-2H-3H by responder would be NF. FYI Mavarako uses strong jump shifts including 2NT to show 16+ HCP hands.

As I posted on Bridge Winners, if one has been the target of a false allegation in a serious matter, then the WBF's statement and condemnation of the communities activities makes perfect sense. Nevertheless, even though I have been the target (non Bridge related) I ask the question: "What was the community supposed to Do?" I fully understand that the evidenced has not been vetted, that withdrawing from the event should not create a presumption of guilt and having credentials revoked doesn't either. However, in the absence of a reasonable process to catch cheats, the community took measures in their own hands. I applaud them for it. But make no mistake about it. We have not yet caught a single cheat. Tom

Both of your statements are correct. In fact, it appears that almost all 24HCP games were bid in the semifinals USA2-Sweden. However, in system building a weak notrump and 4 card major approach with a forcing club, it appears that bidding 24HCP NT games is a requirement. There is no other convenient way to sort out openers rebids. Playing 4 card majors, it seems a requirement to have a relatively light 2/1 structure. We looked at using 1NT as forcing on a 5 card major but that requires opener to bid on hands that belong in 1NT. We tried many structures. In Neapolitan 2/1 was level forcing to 2 NT. However, in Neapolitan we did not open 11HCP semi-balanced hands with a 5 card major that we now feel we need to open. If you do open 11HCP 5 card major hands and bid 2/1 with 10HCP, it appears that 1H/s-2C-2H/s needs to be non-forcing to equalize the 1H/s(5)-1NT(forcing)-2C-2Hs-P auction of 2/1 bidders. If 1Hs-2C-2H/s is NF, opener needs to do something else with 14HCP. That creates a game force. I suspect that not much is unique to Mavarako or any other system. What I am showing is an approach that gets to the 2 level with the HCPs range reasonably defined but the trump fit not defined. Opener's double announces BOTH 14-15HCP AND 4 hearts. A pass confirms 5 hearts in opener's hand. Essentially responder knows the trump fit AFTER the balance. I agree this is not unique. This is actually from 50's Goren when 1NT was 16-18HCP and 4 card majors were opened. You didn't balance quite so often then.

First, my original point is to build a system based on principles you like, not to debate those principles. However, since we are now into principals, I'll continue as I think this is a valuable discussion for those interested. The 24HCP NT game is a function of 4 Card majors and weak NTs trumps. We open light because we ascertained, based on the 2015 team trials that the opponents bidding is less accurate after an opening bid, particularly a non descriptive opening bid like 1NT or the nebulous 1D in precision. A canapé opening (we canapé into clubs) also caused problems. We open a weak NT (11-14) for preemptive value and open a 4 card major with 14-15(16)in preference to a short minor for the same reason. WE also pass a 1NT response to one of a major unless we have either 16HCP or a distributional reason to do so. All this causes problems for the opponents that most pairs are relatively unfamiliar with. So far so good. The 24HCP NT game issue occurs after a major opening and 2NT or 3 level rebid. These bids show [14-15(16)HCP] in opener's hand. The 2/1 showed 10+HCP. That means Mavarako is game forced with 24HCP. Our analysis is that while a 24HCP game is not theoretically sound it is practically sound. Interestingly, in Match Points, where going all out to defeat the contract is not always the goal for the defense, you make 3NT more if you bid it than if you don't. This allows Mavarako to solve many of the rebidding problems inherent in 4 card major openings. The 2/1 bidding sequence is now forcing to only 2 of the Major or a 2NT rebid by responder (or 3 of a suit). This allows Mavarako to gain back against a 5 card major, forcing NT system. Hands that would go 1S(5 cards)-1NT (forcing)-2C(ambiguous)-2S-P go 1S-2D-2S-P in Mavarako. As to the 3 Level, I am speaking of system design, not overall Bridge. That should be obvious. In setting up a system, what system induced problems cost the most Match points or IMPS. It is well known to club bidders that slams with moderately strong hands facing moderately strong hand are often missed by non-club bidders. It is also well known, particularly to canapé bidders, that hands that contain a double fit often produce slams missed by standard bidders (or the wrong slam). However, our analysis says that double part score swings and phantom sacrifices are more important. This appears to be cause by the wide HCP range of standard opening bids and simple overcalls. The wide ranges are tolerated in order to find a fit. When the auction goes 1H(5)-2C(5+ o'call)-2H (3 card support)-3C (3 card support, everyone knows their trump fit and the opponents trump fit but not the HCP strength. The result is that people bid too much and double too little because, under those conditions, it is difficult and dangerous to double. People accept these results as standard not realizing the imps they give up. In Mavarako it would go 1H(4+)-2C-2H(3+[7-9HCP])-3C (3)-X! (14-16HCP 4 Hearts)-p-p-?. Responder has the option to bid 3H or to pass the doubled contract. With 3 hearts he obviously passes. With 4 he makes a decision based on shape.

On 24HCP games -------------- First, if you are watching the Bermuda Bowl, you will see that 24HCP 3NT games are the norm. With HCP splits of 12-12, 13-11 and 14-10, the theoretical percentage of making game varies in the low 40's. However, you no doubt noticed that declarer play is way ahead of defensive play. Numerous times games make when they could theoretically be beaten and rarely does a world class player go wrong as declarer. You see most Bermuda Bowl teams open very light and be very aggressive. Meckstroth opened qx, AKjxx, xx, 10xx 1H and bid 2NT over 2 Clubs. In 3NT the defense can take 5 spades and a Diamond off the top. Mecstroth, of course made it. On opening a club as opposed to 1Nt or the two level and handling competition ----------------------------------------------------------------------------- Second, if you watched the trials (much more civilized time to watch), you saw Berkowitz and Passell fight back from a bid deficit only to lose two slam swings by opening an unbalanced strong NT as opposed to 1C. Take this hand from the BB qualifying. axx x akqx akqxx Two club openers never sniffed the 6D slam. Only two pairs found the slam, one 6 and one 7. However, if you open 1C, overcaller will overcall 1S. Now if you just use a Precision double (5-8HCP) you will never sniff the slam. Club bidders should recognize that making simple overcalls of 1C is pretty standard at the highest level and hone their understandings. In Mavarako, responder would bid 2D (transfer to Hearts, 5 Hearts)-3C (rejecting the transfer) -3D (natural 4 diamonds). The slam is now trivial to bid. Without the overcall it is more difficult. Responder holds: jxx Axxxx j10xx x Over a 1S overcall responder has an easy 2D (transfer) call because the spade overcall increased the chances of a Heart fit. Over 1C, pass, he will need to ungrade his hand. Even if he does the auction is more difficult. 1C-1S-(4+hearts)-2C-2D (retransfer)-3D (refusing transfer). Probably responder bids 3S and opener bids 3NT. On the 3 Level -------------- This quarter final set has been swingy. Not much has happened on the three level. However USA1 did fight back from a big deficit only to lose to part score swings for 9 imps to put the match out of reach. It is true that most IMPS are lost on defense. However IMPS lost from bidding show the majority lost on part score swings as opposed to bid-no bid of games or slams. Choice of games is actually second. Most tellingly, modern 2/1 5 card major bidding is very careful to reveal the extent of a fit. With 3 card support raise a 5 card major. With 4 card support bid Bergen even with 5HCP. If you can't support 1 of a major over 1 of a minor rebid 1NT. If opponents intervene, use support doubles to show 3 card support. Problem is, opponents know the extent of you fit also and almost always balance over 2 of a major. Bottom line the choices become limited. Weak opening bids and weak overcalls allow both partnerships to find their fits but the strength of the hands is relatively undefined. Mavarako reverses this. Strength is narrowly defined but fit is less defined. As Mike Laurence says in his books, 4 card majors are more difficult to balance over. Obviously I can't write a book online. One needs to review the hands, many hands, in detail, and decide what one is comfortable.