Pre-Alerts: "1NT-2
♣ might (but only rarely is) an attempt to play in 2
♦." "Our 1NT overcall is for takeout" "Our jump shifts are fit-based, LR." "our preempts are more aggressive than yours" (I can skip that if I know the players or they're under 50?) "our 1m opening are usually sound" "We play non-Serious 3NT" ... where do you want me to stop?
But of course all of your advanced conventions and treatments are "normal" and don't require a pre-alert, even if they're Bergen, or 2NT rebid not promising a major after Stayman (that doesn't seem to require an Alert either; well, okay, it's a Delayed Alert from partner</sarcasm>), or RKCGerber, or 2
♣-2
♦; 4NT keycard for Diamonds, or...
Yes, poor disclosure is a problem (in fact, there's a whole other thread about poor disclosure of this exact agreement going on right now). But it doesn't get fixed by requiring them to announce something that "never" comes up (once or twice a month?) every round.
There's this attitude around - from the baseline players right up to experts - that "you play it differently than we expect, it has to be a Pre-Alert", but also that "well, that's what everybody (we play with) expects, it's obvious, why do we even have to mention it?" And that just isn't the way Alerts (especially Pre-Alerts) work.
Specifically in the ACBL, the following - only - have to be Pre-Alerted:
- Any system that includes at least one 1-level Opening Bid that is not Natural or that is Forcing.
- Any canape system.
- Playing different systems depending on seat or vulnerability. (It is not considered a different system if the only change is No Trump Range (and responses) or Opening Bid strength.)
- Additionally, you must inform the opponents about any Artificial Opening Preempts below 3NT.
That is, basic system issues that will come up basically every round that will impact understanding of standard auctions. (I will admit, I am surprised that 1NT opening ranges outside of 15-18 don't count as "basic system issues". But they're not, so we don't, unless we're playing known newer players. "we lump a weak call into our invitation, that sometimes other people forget (or even 'forget') to mention" definitely doesn't fit this bill.
When I go to sea, don't fear for me, Fear For The Storm -- Birdie and the Swansong (tSCoSI)