Alerting natural NT bids
There has been some discussion at my club following a Precision 1C opener (alerted and correcly explained on request) and a 1NT response (showing 8-13 balanced). One opponent complained, vociferously, that the 1NT should have been alerted. I found Blue Book section 4C1b a bit ambiguous and not particularly helpful. It talks about "no unusual information about strength". 8-13 isn't unusual to a Precision player but is it sufficiently unusual to an Acol player to warrent an alert? What constitutes "unusual"?
More concerning, the Blue Book says "It must not be forcing unless a forcing situation has already been created", but surely NT bids can easily create forcing situations, not by agreement but by virtue of the number of points revealed.
For example, consider the common Acol sequence of a one level opener, two level response and 2NT rebid. If the 2 level response shows 10+ and the 2NT is 15+, the partnership is known to have at least 25 points so many players would consider the 2NT forcing. However, a forcing situation hadn't been created prior to the 2NT bid so must 2NT be alerted because it's forcing?
In the case in point, I asked the Precision opener whether he considered his partner's 1NT forcing and he said he'd not thought about it but given a minimum partnership combined point count of 24, he thought it almost impossible he would contemplate passing.
Comments
1C (Precision) - 1NT (8+) is alertable if it is forcing (which I think everyone playing Precision thinks it is). The 1C opening is not forcing to game - in fact in most forms of Precision there are some responses which opener can pass. So there's no reason for the opponents to suspect that 1NT isn't a weak bid that could be passed, unless you tell them via an alert that it's forcing.
Sorry if the Blue Book isn't clear.
The intent of "it must not be forcing unless a forcing situation has already been created" was to mean that you alert if it's forcing, unless there's been an earlier bid (typically alerted) which set up a force beyond the level of the NT bid.
I realise that also sounds a bit murky, it's not supposed to be.
The answer perhaps is to give examples:
2C (Acol) - 2S (natural positive) - 2NT
The 2S bid set up a game force, so 2NT is now forcing but doesn't need to be alerted.
2C (Acol) - 2D (negative) - 2NT
Most play 2NT as non-forcing here, so not alertable.
Some people play this sequence as 25+ and game forcing, in which case it should be alerted.
1S - 2C (game forcing, playing 2/1) - 2NT
2C was alerted and explained as game forcing, so 2NT must be forcing but isn't alertable.
1S - 2C (Acol) - 2NT
In old-fashioned Acol, this was not forcing (2-level responses used to be more like 8+ than 10+) and 2NT 15-16.
Or if you play a basic strong NT system, 2NT shows a weak NT and isn't forcing.
You are right that many people today play a 2-level response as rather stronger (say a good 9+) and 2NT as 15+ unlimited, making the 2NT rebid forcing. That is now alertable - there's no way your opponents can know from the auction to date whether you are playing 2NT as forcing or not.
1S - 1NT - 2NT
Some people play this as natural, balanced, 18-19 and not forcing (they can respond very light). This is not alertable.
Some say that 2NT is 18+ and 1NT was 6+ so they have game values, and play 2NT as forcing. This is alertable.
Or as we're talking Precision:
1C (16+) - 1D (0-7) - 1NT is not forcing, not alertable
1C (16+) - 1NT (8+) ; 1NT is forcing, so alertable.
(It's probably worth mentioning that in practice it is going to be pretty rare for the opponents to be damaged by the lack of alert for a natural but forcing NT bid. Artificial NT bids, yes.)