[nige1]

 DavidKok, on 2021-February-07, 15:45, said:

I don't actually play Gazzilli after 1♦-1M, on the grounds that my system is already more than sufficiently complicated. I'm convinced it is very good with an unbalanced diamond (which is what I play) though. My source is Yuan Shen's article, where 1♦-1M; 1NT* shows either 16+ any or 11-15 with 6(+) diamonds, and any other bid denies reverse strength (so 2♣ is 11-15 with 5-4 minors, partnership preference if it shows exactly 5(+)=4(+) or also contains 4=5, and 2♦ shows 11-15 with exactly 4 hearts!).
Of course this particular hand is still troublesome, my comment was slightly tongue-in-cheek. But since you can now systematically distinguish between 11-15 with exactly 4 hearts, by bidding 1♦-1♠; 2♦, and 16+ ('sound reverse') with hearts by bidding 1♦-1♠; 1NT*-2♣; 2♥ you are in a much better spot than many other players would be. I would strongly consider downgrading this particular hand to 15 or so and rebidding 2♦, showing the heart suit.
Something to keep in mind here is that since the 1♦ in this system is 'unbalanced', the 1NT is not needed as a natural rebid. I currently play this rebid as 11-15, exactly 4=5 in the minors (which we do not open 1♣ based on some probabilistic argument), and frankly it is far from ideal. We even considered leaving the sequence meaningless!

I don't see any reason to play something like this over 1♣-1M. For starters both the 1NT and 2♣ rebids are extremely useful as natural bids, and after partner 'accepts' the Gazzilli bid by making the cheapest call available it is too late to stop in your long suit. Also, I have no idea how it would work.

I asked because, for a while, with Steve Male, I played that, for any suit x. 1x- 1N - 2♣ and 1x - 1y - 2♣ is always "Gazilli", showing either 16+ HCP or 6+ x.
Reverses showed shape not power. We didn't explore all the ramifications but our main problem was that we kept forgetting the system.

[nullve]

 DavidKok, on 2021-February-07, 15:45, said:

I don't see any reason to play something like this over 1♣-1M. For starters both the 1NT and 2♣ rebids are extremely useful as natural bids, and after partner 'accepts' the Gazzilli bid by making the cheapest call available it is too late to stop in your long suit. Also, I have no idea how it would work.

IMO the important thing is that the 1N rebid includes balanced hands in a certain range (and possibly some weaker unbalanced hands) and is NF, not that it shows a balanced hand in that range

I play a Gazzilli-like (but NF!) 1N rebid over 1♣-1R(T-Walsh) (an illustration of which can be found in a parallel thread) and some typical sequences are

1♣(1)-1♥(2)
1N(3)-P(4)

1♣(1)-1♥(2)
1N(3)-2♣(5)
P(6)

1♣(1)-1♥(2)
1N(3)-2♣(5)
2♥(7)-P(8)

1♣(1)-1♥(2)
1N(3)-2♣(5)
2♠(9)-P(10)

(1) "10+, NAT(ish) unBAL" OR "11-13/17-19/23+ BAL"
(2) "0+, 4+ S, less than 4 H unless GF"
(3) a) "10-12", 2-S6+C b) 13-15, 22(54) c) "16-18, 2-S5+C, unBAL" d) "17-19 BAL", 2-3 S
(4) wants to play 1N opposite d) (then it's usually ok if Opener instead has a), b) or c). I certainly can't remember the last time it wasn't.)
(5) does not want to play 1N opposite d), wants to play 2♣ opposite a)
(6) a)
(7) c) with 4+ H (Here 2♥ is like a standard reverse over 1♣-1♠ but limited upwards to about 18 hcp and NF)
(8) weak hand with H preference
(9) d)
(10) weak hand with 5(+) S

[DavidKok]

Thank you for sharing. If I understand correctly the NF 1NT 'Gazzilli' bid shows some weak unbalanced hands (10-12 long clubs or 13-15 both minors) or some well-defined strong hands (17-19 BAL or 16-18 with 5+ clubs, which might as well be considered almost the same). Responder assumes the strong version until opener shows otherwise. Compared to T-Walsh where 1NT always shows 17-19 BAL you get more definition in your strong versus weak long club hands, but you might end in a suboptimal spot if opener is weak and unbalanced (for example hand type b might present issues, responder has no way to give preference to diamonds on the 2-level). With hand type c and no second suit (so let's say 6 clubs) do you raise 2♣ to 3♣?
Personally I don't play T-Walsh, but one of the issues I ran into when trying to figure out what T-Walsh would look like is the best methods after 1♣*-1R; 1NT (17-19 BAL). Ordinary NMF/Checkback/XYZ seems adequate but not ideal. Do you run into any issues with responder having both majors on this sequence in your system, or a weak hand with a single major? When, if ever, does responder break the Gazzilli bid with 2♦ and up?

[Vampyr]

We weak notrumpers have it much easier on hands like this. But also I would open 1NT on a similar hand in range.

[gordontd]

 nige1, on 2021-February-07, 13:06, said:

Some partnerships would rather brave the dizzy heights of 3♥ with an 8-card fit rather than play 2♠ (a level lower) in on a 5-1 fit.

It might be the dizzy heights of 4H or 5H if you do it on a much weaker hand than partner will expect.

[nullve]

@DavidKok (minor thread hijack):

Spoiler

 DavidKok, on 2021-February-08, 04:43, said:

Compared to T-Walsh where 1NT always shows 17-19 BAL you get more definition in your strong versus weak long club hands, but you might end in a suboptimal spot if opener is weak and unbalanced (for example hand type b might present issues, responder has no way to give preference to diamonds on the 2-level).

I used to open 1N ("14-16 BAL") with hand type b), but that leads to insolvable problems after Crawling Stayman. Now I play

1♣-1R; 1N-2♣; 2♦ = 13-15, 22(54)

after which Responder can usually place the contract. (Worst case scenario is when Responder has 4423 opposite 2254.)

 DavidKok, on 2021-February-08, 04:43, said:

With hand type c and no second suit (so let's say 6 clubs) do you raise 2♣ to 3♣?

Over 1♣-1♥; 1N-2♣ I do.

Over 1♣-1♦; 1N-2♣ I can choose between

2♠ = "16-18", 3S1-H4-D5+C
2N = "15-17", 2-S2-H4+D6+C
3♣ = "16-18", 2-S2-H3-D7+C.

 DavidKok, on 2021-February-08, 04:43, said:

Do you run into any issues with responder having both majors on this sequence in your system, or a weak hand with a single major? When, if ever, does responder break the Gazzilli bid with 2♦ and up?

Responding 1♦ even with longer S (unless GF values) seems to work well enough constructively.

A few illustrative sequences:

1♣(1)-1♦(2)
1N(3)-2♣(4)
2♦(5)-2♠(6)
P

1♣(1)-1♦(2)
1N(3)-2♣(4)
2♥(7)-2♠(8)
P

1♣(1)-1♦(2)
1N(3)-2♣(4)
2♠(9)-P(10)

1♣(1)-1♦(2)
1N(3)-2♠(11)
P(12)

(1) as above
(2) "0+, 4+ H, may have longer S unless GF values"
(3) a) "10-12", 3-S2-H6+C b) 13-15, 22(54) c) "16-18, 3-S2-H5+C, unBAL" d) "17-19 BAL, 2-3 H"
(4) to play opposite a)
(5) 13-15, 22(54)
(6) 5+ S, to play
(7) "17-19 BAL"
(8) 5+ S, to play
(9) "16-18", 3S1-H4-D5+C
(10) 4+ S, weak
(11) (delayed) INV Reverse Flannery
(12) "10-12", S tolerance (as expected)

 DavidKok, on 2021-February-08, 04:43, said:

Do you run into any issues with responder having both majors on this sequence in your system, or a weak hand with a single major? When, if ever, does responder break the Gazzilli bid with 2♦ and up?

1♣-1♦; 1N-2♥ = "7-12, 6(+) H" ["8-12" might be a better range]
1♣-1♥; 1N-2♥ = "7-9, 6(+) S" ["8-10" might be a better range]
1♣-1♥; 1N-2♠ = "10-12, 6(+) S" ["11-12" might be a better range]
1♣-2♦ = Multi: "4-6", 6(+)M3-OM ["5-7" might be a better range]
1♣-2♥ = Major Flash: "0-3", 6(+)M3-OM ["0-4" might be a better range].

 DavidKok, on 2021-February-08, 04:43, said:

When, if ever, does responder break the Gazzilli bid with 2♦ and up?

1♣-[1M-1]; 1N-?:

(...)
2♦ = ART GF (and the "positive relay" in Gazzilli jargon)
2M/OM: as above
2N = "10-12", 4-5M1-OM
3♣ = "7-9", 4-5M1-OM

(The 2N and 3♣ responses are there just to complete the particular "NT system" I currently use after

1♣-[1M-1]
1N-2♣
2M.)

[DavidKok]

Thank you for sharing!