Duplicate bridge has a basic rule about the auction. Partners may not make bids only they understand. The opponents are entitled to know what you are doing.
Calls are assumed to be standard in meaning. When they are not, opponents must be warned. The bidder’s partner says, “Alert” — period. You do not say more unless an opponent asks for information. If no one asks, further comment is inappropriate. Here are the basics of Alerting
• You are responsible for ensuring that your opponents hear your Alert. If in doubt, pick up the Alert stick (it’s in your bid box) and make sure your opponent sees you wave it.
• When asked about the meaning of an Alert, the bidder’s partner must give a full explanation of the agreement. It is not appropriate to simply state the common or popular name of a convention that is Alertable, such as Flannery (usually five hearts, four spades and 11–15 high-card points).
• The opponents need not ask exactly the “right” question. Any request for information should be answered automatically in a friendly and helpful way with all relevant information. It is unsportsmanlike to give cryptic, evasive or misleading answers in the hope that the opponents will err.
• Either opponent, at their turn, may ask questions if some points are not clear. Note that a player may ask only when it is their turn to bid.
• The standard ACBL convention card has bids in black, red and blue. Those in red require Alerts. Those in blue require Announcements (such as transfer bids when partner opens 1NT o r 2NT- simply say “Transfer.”). Failing to Alert can subject you to penalty, including score adjustments.
• Volunteering information not asked for is a common error made by many new players. When you Alert a bid or call, do not explain unless an opponent asks you to.
If, for example, partner overcalls an opponent’s 1NT opening with 2♣, simply say, “Alert.” Do not say, “Alert. That shows the majors.” This gives unauthorized information to your partner, who may have meant something else and now knows what you took his bid to mean.
Some may say, “I was just trying to be helpful and to speed up the auction.” This is the wrong way to do it and is a definite no-no. It puts partner and opponents in an awkward position, and once it happens, there is no good remedy since the damage has been done.
Bridge is not a game of secret messages. The auction belongs to everyone at the table. Remember that the opponents are entitled to know the agreed meaning of all calls
By Marshall Pearlman