It is only the experienced player who can resist the temptation to
overtrump. The beginner jumps at every trick without realising that
he can often gain by waiting. Overtrump when your hand is weak and
your trumps low; but, if overtrumping takes out your only high card
in the trump suit, especially if it is the commanding trump, it is
nearly always better to discard. Your winning trump is bound to make,
and it is better play to throw away a suit that you can ruff later
with one of your small trumps.
Frequently by overtrumping you make it easy for the adversary to
draw your remaining trumps, which, had you not weakened your hand,
he would be powerless to do. For instance, where you hold the best
and the fourth best trump, with the second and third best in your
adversary’s hand, should you overtrump, your adversary will, of
course, be in a position to catch your smaller trump, while by
refusing the trick you retain the extra trump and are enabled to draw
the adversary’s last trump.