nullve

"Invitational to 3NT -- 2-5 ♣; 2-5 ♦; 2-5 ♥; 2-5 ♠; 17 HCP; 18 total points"

Yes. Unbenownst to the three robots at the table I play 1N-(P)-2♣-(P); ?: 2♦ = one major 2♥ = both majors 2♠: does not exist 2N = no major and 2N-(P)-3♣-(P); ?: / 2♣-(P)-2♦-(P); 2N-(P)-3♣-(P); ?: 3♦ = one major 3♥ = both majors 3♠: does not exist 3N = no major .

Wouldn't you after ♠J-(♠x) ?

Then you risk losing a 5-3 heart fit after e.g. (1N)-P-(2♣)-X (2♦)-3♣-(P), don't you? .

A human and basic robots at a bidding table: [hv=https://www.bridgebase.com/tools/handviewer.html?lin=st||pn|nullve,~~M1363tyl,~~M2945658,~~M7996wdg|md|4S9HA7DAJ654CA6543,SKJ876542HT9DQCKT,SAQ3H642DK932C982,STHKQJ853DT87CQJ7|sv|e|rh||ah|Board%2006|mb|2H|an|Weak%20two%20bid%20--%201-4%20!C;%201-3%20!D;%206+%20!H;%201-3%20!S;%206-10%20HCP;%207+%20total%20points%20|mb|P|mb|P|mb|P|]400|300[/hv] [hv=https://www.bridgebase.com/tools/handviewer.html?lin=st||pn|nullve,nullve,~~M2945658,~~M7996wdg|md|4S9HA7DAJ654CA6543,SKJ876542HT9DQCKT,SAQ3H642DK932C982,STHKQJ853DT87CQJ7|sv|e|rh||ah|Board%2006|mb|2H|an|Weak%20two%20bid%20--%201-4%20!C;%201-3%20!D;%206+%20!H;%201-3%20!S;%206-10%20HCP;%207+%20total%20points%20|mb|P|mb|2S|an|rebiddable%20!S;%2014+%20total%20points;%20forcing%20to%203H|mb|P|mb|3H|an|1-4%20!C;%201-3%20!D;%206+%20!H;%201-3%20!S;%206-10%20HCP;%207+%20total%20points%20|]400|300[/hv] [hv=https://www.bridgebase.com/tools/handviewer.html?lin=st||pn|nullve,nullve,~~M2945658,nullve|md|4S9HA7DAJ654CA6543,SKJ876542HT9DQCKT,SAQ3H642DK932C982,STHKQJ853DT87CQJ7|sv|e|rh||ah|Board%2006|mb|2H|mb|P|mb|2S|mb|P|mb|P|mb|?|]400|300[/hv] 2N = "Unusual notrump overcall -- 5+ ♣; 5+ ♦; 3- ♥; 3- ♠; 14-18 total points; forcing"

As you can see from my previous post, at least the following pairs Edgtton - Hung Byrne - Dyke Bach - Cornell (KO stage) / Bach - Cornell (RR stage) Bakke - Brogeland Livgård - Aa were playing versions of T-Walsh where the transfer is acceped also on some hands with 4c support. For example, Bakke - Brogeland (like Brogeland - Lindqvist earlier) seemed to be playing the dominant "Norwegian" version where 1♣-[1M-1]; 1M = 3 M, not mandatory with 18-19 BAL OR bad 4c 2M raise, usually 11-12 BAL 1♣-[1M-1]; 1M-1♠/N; 2M = the bad 4c 2M raise 1♣-[1M-1]; 2M = good standard 2M raise, 4c support, usually 13-14 if BAL . There are also these famous system notes by Fallenius - Welland where e.g. over 1♣-1♦, 1♥ shows and similarly with 1♠ over 1♣-1♥. So maybe there is also a sizable school that plays the transfer accept the Fallenius - Welland way?

Ok, maybe this is the most common use of the transfer accept globally. But take a look at the convention cards of the pairs that were playing T-Walsh in the Bermuda Bowl: Australia Coutts - Milne Edgtton - Hung China Hong Kong Sze - Chiu England Byrne - Dyke Israel Padon - Birman New Zealand Bach - Cornell (KO stage) / Bach - Cornell (RR stage) Brown - Whibley Tislevoll - Jacob Norway Bakke - Brogeland Livgård - Aa Singapore Maggs - Ng Switzerland Piedra - Zimmermann

How do you define 'Precision'?

Not exactly: https://www.bridgebase.com/forums/topic/83998-the-my-scrapped-bidding-inventions-thread/page__view__findpost__p__1009102 Compared with what? Standard bidding with 1m-1M; 2N = 18-19 BAL, 2-3 M and 1m-1M; 4M: often 18-19 BAL, 4 M is a joke in comparison.

You never open 1♦ on semibalanced hands?

Suppose 1♦ = standard unbalanced with some (41)35 hands added, 1♦-(P/X/1M)-3♣ = "P/C" and that Opener is only allowed to pass the 3♣ response with 5+ clubs. Then the 3♣ response could also be made with only 3 clubs and still be Law-ful.

Maybe not only because I* added the 4135. It's not obvious to me that Responder with that hand (and more generally, on not-so-shapely weak-but-positive hands with 5+ diamonds) should be allowed to say goodbye to 3N at this point even opposite a standard unbalanced 1♦. * or, rather, mw64ahw (I add hands with 10-15 hcp and 1435 in my system)

You'd have Law protection in 3♦.

?

But not necessarily by much, since the opening would always contain a minor and you could play e.g. 1♦-(P/X/1M)-3♣ as "P/C".

why can't a bid be single-suited in the familiar sense and two-suited in the possibly unfamiliar sense of c. at the same time? Is showing length in a suit the same as guaranteeing 3+ cards in the suit? Then the Weak 2♠ opening described by Kantar shows length in two suits, since a hand with 6 spades, 1-3 hearts and 1-4 cards in each minor must have either 6S3y22, 6S3y(31) or 6S4m(21) shape.

It's true of the 2♠ opening in this system that it's weak, promises at least six spades (but also at most six spades) and at least one heart (but also at most three hearts). So why is it not a Brown Sticker?

A Multi 2♦ that includes GF hands with diamonds has been played at the top level for a long time. Convention cards from this year's Bermuda Bowl: Caspersen - Graversen (Denmark) Hult - Bertheau (Sweden) Wrang - Nyström (Sweden) One thing I like about this Multi is that it allows the following symmetry: 2♣-2♦ 2♥-2♠ 3♣+ = GF with primary hearts, unbalanced 2♣-2♦ 2♠-2N 3♣+ = GF with primary spades, unbalanced 2♣-2♦ 3♣+ = GF with primary clubs, unbalanced 2♦-2♥ 3♣+ = GF with primary diamonds, unbalanced

Why not as low as two? Or one? Or zero?

Then what does 'or fewer' in c. refer to?

Does this make any sense at all? I supect (since the intention was to ban Bocchi-Duboin-style canapé overcalls?) that c. isn't about bids that are two-suited in the normal sense of promising at least four cards in two (known or unknown) suits. So is it about weak bids naming two suits, at least one of which can be fewer than four cards long? That is hard to believe, because one could view e.g. a tradtional Weak 2♠ as naming spades and hearts and promising six spades and fewer than four hearts. I must be missing something. Help!

Ekren (or Ekren's) 2♦

Range? Minimum length if < INV? Minimum length if INV? Sets up a force to which contract?

You seem to be claiming that 1) QT9xxx AJ Qx xxx has much lower playing strength than AQJTxx x xxx xxx. 2) While QT9xxx AJ Qx xxx is barely maximum for a Weak 2♠, QT9xxx AQ Qx xxx is worth a 1♠ opening. If so, what do you mean by 'playing strength'? If something like trick expectation, then the Binky values for AQJTxx x xxx xxx and QT9xxx AJ Qx xxx suggest you're wrong about 1). Also, if both 1) and 2) are true, is the former hand actually closer to being worth a 1♠ opening bid?