In many hands the declaration and the cards in dummy will show you
the dealer’s probable strength; and will also suggest the number of
trumps held by your partner.
For instance, should you hold three trumps with three in the dummy,
you cannot expect your partner to hold more than two trumps, allowing
for at least five in the dealer’s hand.
Should you hold four trumps, with three on the table, your partner
cannot have more than one; he may have none.
Although at times you can place high cards in the trump suit, it is
difficult to locate honours in a “no-trump” hand. However, keeping
the general rules for the make in view, you can form some idea of the
adversary’s strength.
When the dealer has passed the make you can often infer from his
subsequent play the absence of certain cards. For instance, should
the dealer, having passed the make, play two aces, he probably does
not hold much strength in the other two suits.