Can a third consecutive pass be alertable?
(Note: this thread isn't about the situation where the bidding starts with three consecutive passes, I'm only interested in the situation where a player ends the auction in some contract.)
With opener vulnerable, the bidding went (1NT), P, (P), P.
I have the agreement with my partner that after (1NT), P, (P), when the opponents are vulnerable, I will pass with strong balanced hands, up to at least 18 points (and probably more, although I haven't had to make that decision yet).
Is this call alertable? Although it's often hard to predict what a "potentially unexpected meaning" is, this probably qualifies – my typical opposition, at least, would be very likely to double with such a hand. On the other hand, the meaning of a third consecutive pass, i.e. "I want to defend 1NT undoubled", is forced by the Laws of the game – you don't really have a choice in what it means.
I guess that one way to look at the situation is that the call itself has its usual meaning – it would be hard for it not to – but the negative inferences from it are different in my partnership to what they would be in other partnerships, because the meaning of the double is different. (I alert the double, of course.) At what point is the meaning of the double weird enough that it makes the pass alertable too?
(There's also the issue of frequency – while the third pass could be a strong balanced hand, it's far more likely to be something much weaker. It seems misleading to alert fringe hand types that a call could have, when it normally shows the same sort of hand that anyone else would have to pass out a 1NT contract.)
Comments
It's a call: it could affect the way your opponents play. e.g. if they play and find your partner with 13 points then they would expect you to have the balance. The alert would tell them that your partner might have more. ergo: it is alertable.
So you alert and say "Could have a strong hand since a double would show ...." to comply with 20F1
It costs nothing.
I just noticed that Blue Book 4H1d has a new exemption as of 2021: "it is not unexpected to pass on a strong hand that would like to double for penalties but cannot do so". I'm not sure whether or not that would apply to this situation.
The alert has been confusing opponents in practice in some auctions, because it's made in a common situation where a low-probability hand is being alerted. (I've been alerting as "either normal pass or penalty X", which opponents have been interpreting correctly, but it's lead to some curiosity.) So I'm not convinced it costs nothing, although I'm still alerting it due to the recommendation to alert in close cases.