SHORT SUITS
There are two lines of play that may be followed to make tricks against the dealer. The first—to make your high cards—has been explained. The second is to make your small trumps by ruffing.
When you have no high card lead, or if you are anxious to be led up to, it is often good play to throw the lead and, at the same time, to try to make your small trumps. This can be done by leading a short suit.
A short suit is a suit of less than four cards; but the term is commonly used to denote a singleton or a two-card suit.
In order that your partner may understand that you are leading a short suit (and not the fourth best card of a long one) it is customary to lead the highest card. (If you are forced to open a suit with K J x, K x x or Q x x, the low card should be led.)
To detect a short suit apply the "Rule of Eleven." If there are (in your hand and the dummy) more higher cards than the rule allows, the lead cannot be the fourth-best card.
Under the following circumstances a short suit should not be led.
If you hold four trumps, including any one honour, don't lead a short suit. Your best play is to open your long suit and force the dealer to trump. In this way you weaken the dealer's hand and you may prevent his bringing in his long suit or you may even establish and make your own.
If the make has been passed, don't lead a short black suit. It is natural to suppose that the dealer is strong in black suits—if in any—and you would be leading up to declared strength.
If you can take the first trick, do so and then judge of the advisability of the short-suit lead.