In a round robin match in the Senior trials, you have to decide how to proceed after partner's 1NT rebid.
E-W vul, North deals. As South, you hold:
1♦: 11-15, at least 2 diamonds. 13-15 if balanced.
1NT: 13-15 balanced (since 10-12 1NT opening non-vul). Will never have a singleton spade. Will never raise on 3.
You play 2-way checkback.
2♣ forces 2♦, after which suit bids are natural invites, 3NT would show 5 spades and be choice of games.
2♦ is game-forcing checkback. Partner will show by priority 4 hearts, 3 spades, a 5-card minor.
2 of a major is to play. 2NT is a natural invite. 3-level calls are natural, slammish.
You have 11 HCP, but great primes. It has to be right to drive to game opposite a 13-15 hand. Best is 2♦, game-forcing checkback. You figure to have a smooth auction which will probably get you to the best game.
You bid 2♦. The bidding continues:
2♦: Game-forcing checkback
2♥: 4 hearts. May have 3 spades, as 4-card heart holding is shown first.
2NT would now be a shape ask. Partner will be able to describe his exact shape without going above 3NT, after which you can place the contract.
Other calls are natural, with natural bidding following.
You can get partner's shape, but that won't necessarily solve your problems. If partner has 3 spades you probably belong in 4♠, but if he has a doubleton spade you might belong in 3NT, 4♥, 4♠ or 5♦ depending not only on partner's shape but his honor concentration. Bidding 2NT will get his shape, but not his honor concentration. You may need partner's cooperation to get to the best game. Your best approach is to bid 2♠. If partner has 3-card spade support he will raise, and you will have found an 8-card spade fit. Otherwise partner will bid a 5-card minor if he has one, 2NT otherwise (or maybe 3♥ with a very strong heart suit). Over 2NT you can bid 3♦, and partner will have a pretty good idea that your hand is something like what you have and he can bid 3♥, 3♠, 3NT, or raise diamonds depending on his honor concentration.
You bid 2♠. The bidding continues:
You have located a 5-3 spade fit. It is possible that 3NT is the best game if partner is 4-3-3-3 with club concentration, but you can't find that out. Spades figures to be the right strain. You aren't strong enough to think about slam, so 4♠ it is.
You bid 4♠ ending the auction.
West leads the ♦7. 3rd and 5th leads. Upside-down count and attitude.
Where do you win this trick, and what do you do next?
There are many things which may have to be done. You will be ruffing at least one diamond in dummy, maybe two. You will want to work on the hearts, leading up to dummy's honors. You may need to take a club finesse.
The best way to start appears to be hearts. If the ace of hearts is onside, you probably won't need the club finesse. It is offside, you may want to take that finesse. Also, if the hearts are 3-3 you may be able to establish the long heart and use it to dispose of a losing diamond.
It is true that if you lead a heart to the king and it holds you might not know where the ace is. However, it will be difficult for East to duck the ace if he has it. He knows nothing about your hand. From his point of view you may have a singleton heart, and that will be consistent with the count card his partner plays.
Another advantage of going after hearts first is that you are likely to get the count of the suit. The defenders will need to know when to take their ace, so the opponent who doesn't have the ace will probably give an honest count signal. This information may be of value later on.
Since you have easy spade entries to your hand, you don't have to unblock the diamond suit first. By playing small from dummy and winning in your hand you conceal your diamond holding. Also, you will find out more about what the opponents have in the suit. Finally, if West happens to have led the 7 from Q107, you will build a third diamond trick.
It probably won't matter which heart you lead. But in general it is right to signal honestly using the enemy methods. Since they are playing UDCA, you should lead the ♥6. This is most likely to confuse them. If they were playing standard signals, you should give your own count honestly by leading the ♥2.
You play small from dummy, and win East's 10 with your ace. At trick 2, you lead the ♥6. West plays the ♥8, and your king loses to East's ace. East returns the ♦4, West playing the ♦5 and you win the king. How do you continue?
With the ace of hearts offside, you now know that taking the club finesse is necessary. If it wins you won't lose a second heart trick, and if it loses you will break even by discarding your losing heart on the ace of clubs. It is clear to come to your hand with a trump and take the club finesse.
While it probably isn't going to matter on this hand, it is generally better technique to win the king of spades rather than the ace. When you win the ace you are pretty much advertising owning the king since you didn't finesse. When you win the king, you might be missing the ace and have king-queen from the opponents point of view.
You lead a spade to the ace, East playing the ♠4 and West the ♠9. You lead a club to ♣9, queen, and ♣3. Now what?
Clearly you are going to discard a heart on the ace of clubs. Then you will be ruffing something to your hand and ruffing a diamond, perhaps cashing the king of spades along the way.
If the hearts are 3-3, it may be helpful to ruff a heart. That will establish the long heart. You will be able to cash the heart and dispose of a losing diamond while an opponent ruffs with a natural trump trick. On the other hand, if the hearts are 4-2 this runs the risk of getting overruffed.
You will certainly be cashing the queen of hearts in all variations. The best technique is to cash the queen of hearts before taking the discard on the ace of clubs. If you play in this order the opponents won't know what you are doing, and might not see the importance of falsecarding in hearts. For example, suppose West has J8x of hearts. If you take the discard first, then when you cash the queen of hearts he will know that it is safe to play the jack which would be consistent with J8 doubleton. But if you cash the queen of hearts first, he will not know that it is safe to dump the jack.
You play the queen of hearts. East follows with the ♥3, and West the ♥4. You cash the ace of clubs, discarding a heart. East follows with the ♣7, and West the king. Now what?
West's king of clubs is probably a falsecard. It is a routine play for a good defender, playing the card he is known to hold.
The heart plays look to be honest. At the point you led a heart at trick 2, West could not foresee that it might be valuable to give false count with 84 doubleton. It would appear to him that the heart count is more important to his partner than to you.
If the hearts are 3-3, you can now ruff a heart and establish a long heart. Since you have two diamonds to dispose of, this looks like a good idea.
You lead a heart. East plays the ♥10. You ruff small, and West contributes the jack. Where do you go from here?
At first it looks easy. Cash the king of spades, ruff a diamond, and pitch your last diamond on the good heart making an overtrick if the trumps split 3-2. But there are possible pitfalls when the diamonds split 5-2.
Suppose East has a doubleton diamond. If he started with 4 trumps you are down, but you could never do anything about that. Otherwise you will lose only one trump trick.
Suppose West has a doubleton diamond. He can ruff ahead of dummy. This will be okay if he started with 2 or 3 trumps, but if he started with 4 trumps he can draw dummy's last trump and you are down.
Since you can afford to lose 2 trump tricks if you can avoid losing a diamond trick, perhaps it is better to lead a diamond before drawing the second trump. This guards against West having 4 trumps and 2 diamonds, since he won't be able to draw dummy's trumps after he ruffs in. The danger is that East has a doubleton diamond and West can overruff the club return and play anothe trump. This would make West's shape 3-3-5-2. It would mean that West had made a dishonest lead of the 7 from QJ765, but we have all seen stranger things.
Go back and check the trump spots. East played the ♠4 and West the ♠9 on the first round. If West started with 4 trumps, those trumps are QJ109. Could you imagine West leading a random doubleton diamond with that trump holding? Not a chance. He would have a routine trump lead. Thus there is no reason not to cash the king of spades. In addition to avoiding going down when West has 3-3-5-2 shape, you will always get an overtrick when the trumps are 3-2.
You cash the king of spades. Both opponents follow. You ruff a diamond in dummy and cash the good heart, pitching your last diamond. All they get is their trump trick, and you make an overtrick. The full hand is:
Do you agree with the opening lead and subsequent defense?
The lead looks fine. It is thematic to lead a short suit when you have a doubleton trump and the opponents are in a likely 8-card fit. That way the defense threatens to get a ruff in the short hand.
East could have given declarer more headaches by returning a heart, but the contract would still have made. However, East's diamond return looks fine. He was hoping his partner had led a singleton diamond. If that were the case, defensive prospects would be quite decent. Declarer might have something like: ♠KQxxx ♥x ♦Axxxx ♣Kx.
It is important to have a sense about when the opponents are likely to be forced to signal honestly and when they know enough to be able to signal deceptively. With this heart suit in dummy it is difficult for the opponents to be deceptive, since partner may need to get the count.
Plus... it's free!