Amazing Deal

Declarer play is completely about planning and execution. By execution, i mean which card to play at which trick (order of play). We all sense the importance of planning because it is required in each and every deal but the execution part is not required in every deal. This deal shows the importance of execution part.
I was kibitzing this deal on BBO.

South is declarer

x x x x
x
Q 9 8 7 x
A x x

K x
A Q x x x x
A 10 x x
x

East is dealer

opens precision 1D

Bidding :
1D-1H-x-P
1S-2D-2S-4D
P-5D-x-ALL PASS

West doubled 5D

Lead was !S by West

small spade and E took it with Ace

and returned a !D, now plan the play
by yourself before seeing the solution.

Assume West to be having K J x of Diamonds for his double.
Losers: Spade Ace, Diamond King. You need to ruff 4 losers from dummy, but if u ruff 4 losers, you have to give two Diamonds losers to K and J. So, this is not a feasible line. The alternative line is dummy reversal in which u need to set up Hearts. Playing for !H to be 4-2 is much better option because East opened precision 1D and is most likely known to have a singleton in Diamonds. So shape of his hand is 4-4-4-1. You can ruff at most one two hearts in dummy due to communication problem, so best line is to finnese in Hearts. So, duck the Diamond, West takes it with Diamond K and returns a !S. Take it with King and play a club to Ace, Heart finnese, then Ace and ruff a Heart. Now play Diamond to the Ace, ruff another Heart, draw the last trump and enter the hand in Diamonds and cash ur Hearts to make the contract.
Here planning was very important. You could also ruff a club instead of playing Diamond to the Ace, ruff a Heart, then draw trumps by first playing Diamond Queen and then Ace ending in hand and cash ur Hearts.

Now lets see the scenario of a Club lead (the best for defence). Lets see what happens if we follow the same line of play. Take Club Ace. Heart finnese and cash Heart Ace. Now ruff a Heart. Low Spade to the King , but East will go up with Ace and return a low club which u have to ruff in hand. Ruff another Heart. Current Position is:

x x
-
Q 9 x (Dummy)
x


K
x x
A 10 x (Hand)
-


U r in dummy now and cant cash your Hearts. When declarer ruffed two Hearts, West discarded his two Spades and he is now void in Spades. Try to enter hand with D Ace. Now u can cash ur Hearts and West is unable to ruff, if he ruffs dummy will overruff. But this line fails if West started with K x in Diamonds and East with J x in Diamonds because East will ruff when u play Hearts.
Instead of playing spade after first heart ruff, if declarer tries for second Heart ruff by going to hand via Club ruff, then he will always be down because he will be short-trumped and wont be able to enjoy his Hearts.

Alternative line of play is :
After taking Club Ace, take Heart finnese, cash the Heart Ace, ruff one Heart and play a Spade.
Suppose East takes Spade Ace and returns a club, ruff it in hand. Now don't ruff one more Heart (the reason will be given later). Play low Diamond to Queen.
Various Scenarios:
1) Suppose West ducks Diamond King, then take it with Queen and return to hand with Diamond Ace.
Now u can cash Hearts. When he ruffs with master trump, u have still 2 more entries to cash the Heart.
2)Suppose West goes up with Diamond King, and returns a Club, ruff it in hand cash Diamond Ace. Now there is one more Diamond outside and two more in dummy.
Now can u see why not ruff the second Heart earlier? So that, u can enter the dummy by ruffing second Heart and draw the last trump. Now enter hand with Spade King and cash your Hearts.

The most important thing in this hand was delaying the second Heart ruff to make the contract cold.
This hand shows why u should not neglect the execution part of dummy play.