[DavidKok]

 giorgis_di, on 2023-October-16, 06:37, said:

I forgot to add that I haven't think about how to deal with inference. For instance, if the LHO doubles, then my partner's 2♣ is perceived as a strong hand (otherwise she/he could pass). Definitely, the situation becomes more complex if the LHO overcalls at 2. One option could be that x by my partner to show a strong hand (17+ hcp), but really haven't thought a lot the inference part.

Also, in your example would you open 3D with the following hand x xx Kxxxxxx xx? Probably not, and so in that case you still cannot preempt at 5D. On the contrary, by opening 1NT you may be able to do it

I think you are missing the point in a number of ways.
Most auctions these days are competitive (approximately 55%-75% of all auctions, depending on who is counting and what the event is). Having some sense of how to have constructive auctions but not competitive auctions will get absolutely crushed in play. Some warning signs include

• Nebulous opening bids (ones that do not name length in a suit or a short list of similar hand types), particularly those that can both have very little playing strength (such as the 12-14 notrump) as well as strong shapely hands.
  
• Great discrepancy in opening frequencies. Typically in competitive auctions it is best for all low level bids to have near-equal frequency (some people mistakenly believe that higher bids should be significantly less frequent, either halving each step or going down with approximately a factor 1.618, following the Fibonacci sequence. This is nice for constructive auctions but false when we expect the opponents to bid) to convey maximum information should the opponents bid again.
  
• Multiple hand types in a bid facing which partner should evaluate their hand very differently. In this case your 1♣ contains specific balanced hands, unbalanced hands with long diamonds, and unbalanced hands with long clubs. The value of partner's minor suit holdings in particular varies wildly facing these three hand types, and this will make it near-impossible for partner to accurately judge the value of their hand in competition.

All these problems exist to a great degree over your 1NT opening as well. Since the hands in the opening are so weak the opponents are very likely to make a 2-level overcall, and partner will be in a very tough position without knowing your suit.
It is a classic mistake to write up a lot on constructive auctions and neglect competitive auctions. You are in good company - many system enthusiasts make this mistake. And many of them are easy pickings at the table as a result. Personally I think the focus should be inverted - competitive auctions happen more frequently, and the stakes are generally higher. So it is most important to get them right, and bidding systems should focus primarily on how to deal with competitive auctions, and only secondly with constructive auctions. Put slightly differently, any of a range of modern systems is 'good enough' to get the majority of uninterrupted auctions right, but the competitive agreements are all over the place. I don't really care for your system of continuations of the 1NT opening without competition, but I am very eager to see how you will deal with 1NT-(2♥)-?, and doubly so with 1♣-(1♠)-<something>-(2♠); ?.

Lastly I think your example hand is close between 3♦ and 4♦.

[giorgis_di]

 DavidKok, on 2023-October-16, 07:47, said:

I think you are missing the point in a number of ways.
Most auctions these days are competitive (approximately 55%-75% of all auctions, depending on who is counting and what the event is). Having some sense of how to have constructive auctions but not competitive auctions will get absolutely crushed in play. Some warning signs include

• Nebulous opening bids (ones that do not name length in a suit or a short list of similar hand types), particularly those that can both have very little playing strength (such as the 12-14 notrump) as well as strong shapely hands.
  
• Great discrepancy in opening frequencies. Typically in competitive auctions it is best for all low level bids to have near-equal frequency (some people mistakenly believe that higher bids should be significantly less frequent, either halving each step or going down with approximately a factor 1.618, following the Fibonacci sequence. This is nice for constructive auctions but false when we expect the opponents to bid) to convey maximum information should the opponents bid again.
  
• Multiple hand types in a bid facing which partner should evaluate their hand very differently. In this case your 1♣ contains specific balanced hands, unbalanced hands with long diamonds, and unbalanced hands with long clubs. The value of partner's minor suit holdings in particular varies wildly facing these three hand types, and this will make it near-impossible for partner to accurately judge the value of their hand in competition.

All these problems exist to a great degree over your 1NT opening as well. Since the hands in the opening are so weak the opponents are very likely to make a 2-level overcall, and partner will be in a very tough position without knowing your suit.
It is a classic mistake to write up a lot on constructive auctions and neglect competitive auctions. You are in good company - many system enthusiasts make this mistake. And many of them are easy pickings at the table as a result. Personally I think the focus should be inverted - competitive auctions happen more frequently, and the stakes are generally higher. So it is most important to get them right, and bidding systems should focus primarily on how to deal with competitive auctions, and only secondly with constructive auctions. Put slightly differently, any of a range of modern systems is 'good enough' to get the majority of uninterrupted auctions right, but the competitive agreements are all over the place. I don't really care for your system of continuations of the 1NT opening without competition, but I am very eager to see how you will deal with 1NT-(2♥)-?, and doubly so with 1♣-(1♠)-<something>-(2♠); ?.

Lastly I think your example hand is close between 3♦ and 4♦.

Personally, I don't know a lot of players opening such a hand, neither 3 nor 4 of ♦. Also, you ask how I handle some auctions, so here some more thought:

1. 1NT - x :
a. passing, nothing to say, a hand at most of 16hcp
b. any bid at 2 shows a strong (17+hcp) hand, with its own long suit (specified by the bidding)
c. xx = strong hand, balanced, mostly asking for opener's long suit

2. 1NT - 2-level overcall:
a. passing, nothing to say, a hand at most of 16hcp
b. x strong hand, asking for opener's longest' suit
c. new suit, strong hand with 6+ solid cards (depending on the vulnerability)

For your 2nd quiz ( with 1♣-(1♠)-<something>-(2♠) I cannot really reply because 1♣ can contain many hands and also, it depends on what this "something" is. For instance

something = 2♣:

a. 3♣ = to play
b. x = invitational, asking for stopper in ♠
c. 2NT = invitational with stopper

something = 2♦:

a. x = 3 cards support
b. 2NT = invitational: Bid 3NT if you accept and has a stopper, or 3♠ if you accept by asking for stopper, 3♦ = to play

[straube]

 DavidKok, on 2023-October-16, 07:47, said:

[*]Great discrepancy in opening frequencies. Typically in competitive auctions it is best for all low level bids to have near-equal frequency (some people mistakenly believe that higher bids should be significantly less frequent, either halving each step or going down with approximately a factor 1.618, following the Fibonacci sequence. This is nice for constructive auctions but false when we expect the opponents to bid) to convey maximum information should the opponents bid again.

I agree the opening bid frequencies should be much flatter than Fibonacci would suggest, for competition preparedness and other reasons.

[Gilithin]

The most logical response structure is to use either 2♠ or 2NT as a forcing relay in combination with ParadoX. After 1NT - 2♠, something like 2NT as any max (GF) and bidding the long suit with a minimum is a simple way of handling invite+ hands. As such, dealing with 2 level interference of the 1NT opening should not be a significant issue. 3 level interference does require some attention but I would think most opponents will play jump overcalls as strong, which limits the difficulties. What you do have to address thoroughly is interference of those openings that become overloaded or nebulous. This tends to be the area where these types of system fail.

[giorgis_di]

 Gilithin, on 2023-October-16, 12:23, said:

The most logical response structure is to use either 2♠ or 2NT as a forcing relay in combination with ParadoX. After 1NT - 2♠, something like 2NT as any max (GF) and bidding the long suit with a minimum is a simple way of handling invite+ hands. As such, dealing with 2 level interference of the 1NT opening should not be a significant issue. 3 level interference does require some attention but I would think most opponents will play jump overcalls as strong, which limits the difficulties. What you do have to address thoroughly is interference of those openings that become overloaded or nebulous. This tends to be the area where these types of system fail.

2♠ or 2NT are valuable alternatives. I agree that 1♣ and/or 1♦ are more problematic and definitely require more attention on how to handle inference

[fuzzyquack]

Many players relatively new to the game think they may kill it by adopting a home-cooked exotic bidding system. That's the worst way to successful bridge.

[mw64ahw]

 fuzzyquack, on 2023-October-16, 15:00, said:

Many players relatively new to the game think they may kill it by adopting a home-cooked exotic bidding system. That's the worst way to successful bridge.

Maybe some people just like playing around with alternative ideas; some ideas get tossed aside, some may become mainstream and a few even become standard.

[Gilithin]

 fuzzyquack, on 2023-October-16, 15:00, said:

Many players relatively new to the game think they may kill it by adopting a home-cooked exotic bidding system. That's the worst way to successful bridge.

One of the reasons players interested in bidding theory look for better ways of doing things is to avoid auctions like:

 fuzzyquack, on 2023-October-16, 14:57, said:

1C/1N-7H

[helene_t]

We have previously had discussions about a 1NT opening defined as a bad weak 2M OR 15-17 balanced. So you can have it both ways. If responder has no game interest opposite the 15-17 bal AND doesn't have a 5-card major, they just pass. 1NT-5 is ok as long as it isn't doubled.

1♦ is underloaded. You shouldn't define a 1-of-a-suit opening as specifically a balanced hand with a narrow range, that will lead to overload elsewhere in the system.

It is unclear what you do with an unbalanced hand with diamonds, or with both minors. It is also unclear what to do with 12-14 bal.

[giorgis_di]

 helene_t, on 2023-October-17, 04:48, said:

We have previously had discussions about a 1NT opening defined as a bad weak 2M OR 15-17 balanced. So you can have it both ways. If responder has no game interest opposite the 15-17 bal AND doesn't have a 5-card major, they just pass. 1NT-5 is ok as long as it isn't doubled.

1♦ is underloaded. You shouldn't define a 1-of-a-suit opening as specifically a balanced hand with a narrow range, that will lead to overload elsewhere in the system.

It is unclear what you do with an unbalanced hand with diamonds, or with both minors. It is also unclear what to do with 12-14 bal.

The easiest part is the 12-14 balanced. I open 1 club and rebid 1nt, nothing special.

The other two are more complex and you are right. One solution could be to open 1 club and rebid 2 diamanods. This is not a reverse since 1 club opening may contain more diamonds than clubs

[mw64ahw]

If you want to bid on nothing you try a strong pass approach