[Kungsgeten]

I haven't seen many systems using an artificial 1NT opening (I think Romex is the exception). Woolsey in his "grunt defense" to nebulous minors play a 1NT overcall as 4M and 5+m (may be the suit opened). I wonder if this could work as an opening bid? It could lead to some interesting structures like:

1C = Strong
1D = Weak NT, 4441 or 6+m.
1M = 5+M
1NT = 4M and 5+m.
2C = Minors.

[Cyberyeti]

I used to play a home hashed system with a "big unbalanced" 1N which was a lot of fun, but yes there aren't many

[pescetom]

Cyberyeti, on 2022-March-16, 05:15, said:

I used to play a home hashed system with a "big unbalanced" 1N which was a lot of fun, but yes there aren't many

The Vienna system had 1NT as a catch all for all strong hands, not dissimilar to a mainstream 2♣ opening (and gaining a 2♣ response which could allow a more rational dialogue, although I suspect it was just used to show clubs).

[nullve]

Kungsgeten, on 2022-March-16, 04:33, said:

I haven't seen many systems using an artificial 1NT opening (I think Romex is the exception).

Not true!

Kungsgeten, on 2015-November-15, 16:35, said:

A third solution, used by a Swedish pair during the Bermuda Bowl this year is to use 1NT as both minors (5-4 or better).

Other systems:

Arno Club (= Little Roman)
Boring Club
Midmac
Moscito (Honeymoon, 90s, Terrorist, ...)
Vienna

[Cyberyeti]

pescetom, on 2022-March-16, 10:01, said:

The Vienna system had 1NT as a catch all for all strong hands, not dissimilar to a mainstream 2♣ opening (and gaining a 2♣ response which could allow a more rational dialogue, although I suspect it was just used to show clubs).

We decided to play 1♣ as (among other things) most balanced hands (other than the one range in 1♦) including all the strong ones hence 1N was always unbalanced.

[nullve]

Kungsgeten, on 2022-March-16, 04:33, said:

1NT = 4M and 5+m.

Then, if

1N-2♣ = GF relay,

maybe

1N-2♣; ?:

2♦ = 5+ C, not high (= S) shortage if 4 H
...2♥ = relay
......2♠ = 4H5+C, low (= D) or even shortage
......2N+ = 4S5+C
2♥ = 4S5+D
2♠ = 4H5+C, high (= S) shortage
2N+ = 4S5+C

?

[helene_t]

pescetom, on 2022-March-16, 10:01, said:

The Vienna system had 1NT as a catch all for all strong hands, not dissimilar to a mainstream 2♣ opening (and gaining a 2♣ response which could allow a more rational dialogue, although I suspect it was just used to show clubs).

Actually, 2c was a negative relay. 2d was a GGF relay.

[Kungsgeten]

Thanks for mentioning other artificial 1NT openings!

nullve, on 2022-March-17, 01:44, said:

Then, if

1N-2♣ = GF relay,

maybe

1N-2♣; ?:

2♦ = 5+ C, not high (= S) shortage if 4 H
...2♥ = relay
......2♠ = 4H5+C, low (= D) or even shortage
......2N+ = 4S5+C
2♥ = 4S5+D
2♠ = 4H5+C, high (= S) shortage
2N+ = 4S5+C

?

My first thought was to play 1NT-2♣ as "pass or correct", but I think it might be better as an asking bid, but possibly weak. Perhaps:

1NT-2♣;
2♦ = Natural. 2♥ is pass/correct, while 2♠ could be GF relay (unfortunately a bit high*) and 2NT maybe INV relay.
2M = Natural and 5+♣.

* Another option is to give up playing 2♥ here, and use 2♥ as the relay, and 2♠ as pass/correct.

Now I don't know if the opening itself has merit. I've seen 1♦ played as basically the same thing, 1NT is more preemptive but leads to problems for both sides.

[pescetom]

helene_t, on 2022-March-17, 07:59, said:

Actually, 2c was a negative relay. 2d was a GGF relay.

Thanks for that.
I haven't really thought it through, but first instinct is that it might be better to invert the two, maybe with 2♣ as a Marionette over which responder can show his own suit if opener so wishes.

[straube]

Kungsgeten, on 2022-March-16, 04:33, said:

I haven't seen many systems using an artificial 1NT opening (I think Romex is the exception). Woolsey in his "grunt defense" to nebulous minors play a 1NT overcall as 4M and 5+m (may be the suit opened). I wonder if this could work as an opening bid? It could lead to some interesting structures like:

1C = Strong
1D = Weak NT, 4441 or 6+m.
1M = 5+M
1NT = 4M and 5+m.
2C = Minors.

This presumably has two NT ranges 12-14 and 15+ instead of 11-13, 14-16, 17+. That's a huge loss imo.

Opening 1N could have wins when responder has both majors (1N-3H could be p/c) or both minors (1N-3C =p/c) but is awkward otherwise. You're "paying" a lot for knowing pd has a 5m when the most important thing is the major suit fit. To contrast, my system goes 1D-1H, 2H to show a weak NT with 4H and 1D-1H, 2D to show 4H, shortness and minimum. Sure, I can ask that shortness or pattern opener's hand but most of the time would not do so. Fit and strength is usually enough.


2C minors would often lose a superior major suit fit at the 2-level. 2C-2D has to be a preference and 2C-2H would (I suppose) need to be an ask of some kind. So you can't stop in 2H when responder has heart length. You can't find a major suit fit when partner has 5S/4H (and could have responded 2H to 1D to show this pattern...or 1D-1S, 2C-2H if 1D-2S were weak and 1D-1S, 2C-2S were an artificial ask (as I think awm and Sieong use).

[Gilithin]

If you have 1NT free, it might make sense to use it for completing the preempt tree, for example:-

1NT = ♣ or ♦ or ♥+♠
2♦ = ♥ or ♠
2♥ = ♥+minor
2♠ = ♠+minor
2NT = ♣+♦

When I read the title, I rather assumed you were talking about using 1NT to show a weak 4M-5m hand as an inverse to the 5M-4m hands in Muiderberg. I don't really get the advantage or switching the minimum balanced hand and the 4M-5m hand type between 1NT and 1♦. 1NT natural tends to be quite effective...