This chapter covers our carding agreements: what our opening leads mean and what our signals mean. None of this is bidding, so it is all prose. It is split into leads (against suit contracts and against notrump), and signals (attitude, count, and suit preference).
From length, we lead 3rd-and-low. The one real exception is when we have supported partner's suit; there we may lead a more attitude-style card, high from a small holding and low from a holding with an honor.
Our default honor lead is the ace from ace-king. If we have promised 4 or more cards in a suit during the auction, we switch to Rusinow honors in that suit, meaning we lead the second-highest of touching honors. A transfer promises a suit, so it turns Rusinow on. A negative double does not promise any one suit, even the other major, so it does not. A takeout double is presumed to claim no suit.
Signals to our honor leads are generally attitude. If attitude is already known, they may switch to suit preference. For example, after a diamond opening and a heart response that gets doubled and raised, whichever hand is on lead leads Rusinow honors in hearts.
Our spot leads are American 2nd-and-4th: 2nd or 4th highest from 4 or more cards, and top of a holding of 3 small or fewer. As against suits, we may vary this in partner's suit. We may also lead low from three small in some spots to show length, a good example being after an unsupported weak two.
When dummy wins the trick and third hand gets to signal, the signal is count if dummy's winning card is a queen or lower, and attitude if it is a king or higher. For this rule, dummy is presumed to play the lowest of touching cards, so if dummy holds KQx and plays the king, we still treat dummy as winning with the queen, and therefore the signal is count.
Honor leads against notrump are Rusinow from the queen down to the nine, with the eight as the pivot card. The nine promises the ten or shortness; the eight may or may not hold the nine. For this purpose "shortness" means fewer than 4 cards, so we still lead the queen from QJx. We also lead the queen from KQx to avoid the power lead, though this is a rare exception.
The ace from ace-king is the default honor lead. The king is the "power" lead, asking for count or unblock, for example from KQT9. Signals to our other honor leads are generally attitude about the honor just below the card led.
Leads in the middle of the hand are generally attitude. When we judge that count matters more, we keep playing 3rd-and-low against suits and 4th against notrump.
Against notrump, if we win the opening lead and return the suit, we play our lowest remaining card from 3 or more and high from 2. We might also lead a high card to hold the lead, and that can be done with any number of cards. Honor leads later in the hand revert to standard.
Our general carding is upside-down count and attitude, and standard (right-side-up) suit preference.
When partner is on lead, our priority of signals is attitude first, then suit preference, then count. When we are following suit, the priority is suit preference, then count. We give count when it is necessary, but most cards we play while following suit are suit preference or just a spot with no message. Discards are generally attitude.
Standard suit preference means a high card asks for the higher suit and a low card asks for the lower suit. This is often enough when one suit can be ruled out, such as trumps. A middle card is sometimes used to encourage continuing the suit led despite a normal suit-preference situation, for example when there is a singleton in dummy, or to encourage a trump shift.
In other situations, such as following suit, there are often three live suits. Sometimes one suit can be inferred to be unreasonable. Otherwise we encode preference by the order in which we play our spots.
With two cards to signal, high-then-low points to a high or middle suit, and low-then-high points to a low suit or shows no preference.
With three cards to signal, we always start with the suit we want partner to lead, and the more "active" we are (playing higher spots earlier) the more we like that suit. Reading L as low, M as middle, and H as high, the order encodes:
The idea is that starting with the target suit and then playing a higher spot next shows we are actively signaling, so even if we never complete the sequence partner already knows we are interested in something.
Signal with the clearest card you can. Subtle carding can be elegant, but there is real danger that partner misreads it, and a direct signal in the suit you care about beats several layers of indirection. Two hands from the 2019 San Francisco NABC BAM cost us tricks precisely because a subtle attitude or suit-preference card was read the wrong way; in each case a plainer signal would have gotten the message across.