Winning tricks by ruffing and the dummy reversal
Most of the time extra tricks come from ruffing in the hand that is short in trumps. A dummy reversal is a declarer play technique in bridge where we ruff in the hand with long trumps and then draw trumps in the other hand.
Ruffing in the long hand usually doesn't help
Ruffing in the hand with the most number of trumps is usually fruitless as declarer because we'll make those trumps anyway. One situation where it can work to ruff in the long hand is the dummy reversal.
We're in 4♥ and West leads the ♠K. Let's count tricks. We're going to make the ace king, queen jack, ten nine of hearts. So that's six heart tricks. We're going to make the ace of spades. That's seven. And we're going to make four club tricks. So that's 11. 11 tricks.
Focus on the heart suit. I said we were going to make six heart tricks. What happens if I play the ace of spades? Now I can ruff a spade here because we are supposed to get extra tricks if we ruff things. So I'm going to ruff a spade with the nine of hearts. Now I can draw trumps, but we end up making the same number of tricks because I ruffed a spade with a trump that I was going to make anyway. We already counted six heart tricks.
Winning extra tricks by ruffing in the short hand
Let's try another 4♥ contract. West leads the ♠K so let's count our tricks. We've got five heart tricks. ♠A is six. We're going to make three club tricks so that's nine. This time though, I can get extra tricks by ruffing spades because I'm ruffing with trumps that I hadn't already counted. So I've already counted five heart tricks. I'm going to ruff a spade with a heart. So I've made one heart trick and I'm still going to make those five heart tricks in my hand.
We get extra tricks by ruffing in the hand with the least number of trumps and drawing trumps with the hand with the long trumps.
But I've got another hand to show you. Supposedly we can only get extra tricks by ruffing in the hand that's got the least number of trumps. So here maybe I can get an extra trick by ruffing something in the dummy. I'm not sure what, maybe a diamond, I guess I could play ace of diamonds, lose a diamond, and then eventually ruff a diamond with one of my hearts. But on this hand, there's another way we can do things.
North's trumps are so good that we can use the king, queen jack of hearts to draw trumps and we can ruff three times in the south hand. I'm going to play ♣A, cross over to the ♠A, and I'm going to ruff a spade. I'm going to cross over to the KC, ruff a spade. So I've ruff twice. Now I need to get to the North hand, so I'm going to play over to the heart and I'm going to ruff another spade. So that's three ruffs.
I'm actually going to ruff that last trick with the ♥A because I need to use my nine of hearts to get back over to draw the trumps. My nine of spades is now a winner and I've still got the ace of diamonds. We end up with 11 tricks. That technique of ruffing in the long hand is called a dummy reversal. It doesn't come up that often, but when it does, it's really neat.
I remember really struggling with ruffing, cross ruffing and anything to do with the trump suit. Still challenging!