BRIDGE NOTES: The expert is a confirmed pessimist

In Bridge the play that gives the declarer the highest odds of success should be given the top priority. Of course, the opponents' bidding can alter the odds depending on the bids made and by which particular defender. Let us learn by example. North South land in 4H instead of the lay down 3NT, holding the following cards:
The bidding:
The opening lead from west is 4H. East follows with the 9. Place yourself in the south seat and plan your play.
On surface counting your solid tricks, you have 9 tricks -5 heart tricks, 3 side aces, KC. The tenth can either come from the club finesse of the queen by playing the JC on leading low from dummy or a double finesse on spade split honours, placing the QS in one defender's hand and the KS in the other defender hand even both KQ of spades with west can yield 2 spade tricks - a 75 percent chance.
But there is always more to it in Bridge than meets the eye. Can you find a better line of play, one with more odds of success? Being a pessimist in Bridge is sometimes a guarantee for success? Well what better line, is there for the declarer? The opening lead gives a clue that west does not have all 3 diamonds honours for otherwise he would surely have lead from KQJ. That leaves east with a holding of one honour at least if not 2. That should be enough to guarantee the contract, how?
Yes, by elimination. After 3 rounds of Trumps is played east discarding a club and a spade. The diamond suit needs to be carefully handled. Playing towards the table, you need to insert the 10D if west plays low. For up to this trick you have to keep west out of lead. If west inserts say the JD, you can win with the ace and now play 3 rounds of clubs ruffing in hand and spinning the club finesse of the queen.
A further diamond play would leave. West-east with the following cards left while NS hold as under:
As you can see, it does not matter who wins the third diamond for west east held the following hands:
Suppose west wins the third diamond led with the king, he would then have to return a spade allowing east to win the trick with the QS. What can east do best? At most east can cash another diamond but must then return a spade into dummy's tenace or concede a ruff and sluff.
Let us now revert back to the position where supposing west plays lows on the first round of diamonds. The resulting position would more or less remain the same. The contract of 4H would become ice clad. You see anyone can make a contract when all finesses are right and the suits break kindly. But when conditions are not that conducive, a player's true skill is put to best and only by taking timely precautions can he nullify or at least mitigate effects of the bad breaks like in the above illustration. The expert play was based on the assumption that all cards are unfavourably placed with the finesses likely to fail. This shows that the expert is a confirmed pessimist!

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  NORTH           SOUTH
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   A Q 4         J 10 6
J 10 8 6      A K Q 5 3
  A 10 2          7 5 3
   A 7 3            K J
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 N    E     S         W
 P    P    1H         P
2H    P    4H  All Pass
=======================

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North    West    East    South
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  A94   8 5 3   K Q 2   J 10 6
   10     -       -          Q
  102     K 8   Q 9 6      7 5
   -       10     -          -
          J 3
==============================

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   WEST         EAST
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  8 5 3       K Q 72
  7 4 2            9
  K J 8      Q 9 6 4
Q 10 84      9 6 5 2
====================