[AL78]

I'm having thoughts as to how I can improve my defence which has holes in it (lack of knowledge/experience of deep third round signals is one example). The way I was thinking of doing this is to look at the hands where I was defending, and look further at the boards where we got a poor score. I am trying to establish if there is a common factor in defence that is causing us to leak tricks. This sounds a very simplistic way of doing it and might not be very revealing in the end, so does anyone here have any better suggestions? For example, I'm wondering if on a few hands, what looks like a choice of two reasonable plays based on the information I have gathered is not a guess, but I choose the wrong action because I have missed something like an additional piece of information or inference.

Is it also worth looking at the boards where we got a good score?

I think I would get more enjoyment out of the game if I could up my strength and have more confidence in myself. A strong defender can swing the axe when the opponents are taking liberties with wild bidding and reap the rewards. Sometimes I manage the first without the second.

[DavidKok]

I do not have a clear answer to your question. But I do have some suggestions, some of which may be useful:

• You can use a double dummy solver (or GIB, or the likes) to go through hands trick-by-trick and see which plays cost a trick, and maybe figure out why. Generally basing your expectations on double dummy play is ill-advised, but it at least combines some objective standard for the quality of the defence with an easy to access trick-by-trick evaluation.
  
• There are several books on defence that explain the thought process of good defenders in great detail (including which inferences to draw). You can learn from these and compare them with your own thoughts while playing.
  
• Experienced players can help you point out which plays were a mistake and which were good, and why. It can be challenging to get an objective evaluation though, especially if they have already played or seen the hand.

[AL78]

DavidKok, on 2022-July-12, 12:58, said:

I do not have a clear answer to your question. But I do have some suggestions, some of which may be useful:

• You can use a double dummy solver (or GIB, or the likes) to go through hands trick-by-trick and see which plays cost a trick, and maybe figure out why. Generally basing your expectations on double dummy play is ill-advised, but it at least combines some objective standard for the quality of the defence with an easy to access trick-by-trick evaluation.
  
• There are several books on defence that explain the thought process of good defenders in great detail (including which inferences to draw). You can learn from these and compare them with your own thoughts while playing.
  
• Experienced players can help you point out which plays were a mistake and which were good, and why. It can be challenging to get an objective evaluation though, especially if they have already played or seen the hand.

Thanks.

Do you have any recommendations for books on defence.

I guess with point 3, I could selectively post hands on here where I apparently had a choice of plays and chose the one that blew a trick, and see what others would have done at the critical time.

[jdiana]

A few thoughts:

1. Defense is, of course, a partnership undertaking so if you have a regular partner, I suggest working on this together. Having good written agreements for defense is helpful.

2. I agree with David that double dummy analysis can be useful in some ways, for example in looking at opening leads.

3. BBO Helper has some very useful features including listing the opening leads for each board and providing a view where the boards are sorted by auction. I've been lazy about doing this myself, but I think it would be helpful to isolate the boards where other people defended the same contract, after the exact same auction, to see what they did differently. Since the information we get from the auction affects our defense, I think this will help compare apples to apples.

As for book recommendations, Eddie Kantar's books on defense are probably a good place to start.

Good luck!

[mikeh]

I would advise against using double dummy analyses to ‘improve’ your defence

The Bird and Anthias books on leads are very good, so long as one is careful to appreciate that the double dummy nature of the project makes some of the results debatable. However, they deal only with the opening lead and, moreover, they simulate 5,000 random hands (constrained so as to match the auction…a source of weakness that, imo, they don’t adequately address).

It’s unlikely that you could or would want to simulate your defence across 5,000 hands😀

Furthermore, it takes significant discipline, and bridge knowledge, to recognize when a simulated defence (that works) is actually a bad but lucky line…mistaking the ‘winning’ line for the ‘correct’ line is a very common error, made all the more so if your skill level is such that the better, although on this hand failing, line escapes you.

Imo, the best advice anyone can give you, short of playing with an expert and reviewing hands with him or her….for some number of hands in the several hundreds….is to read.

I’m not familiar with current publications in general…most books are aimed at the advancing player…and rightly or wrongly my advancing days (rather than my advancing years) are pretty much behind me.

So you may have some difficulty finding these but I strongly recommend Hugh Kelsey. Killing Defence is superb, and it’s sequel, More Killing Defence is just as good.

His simulated team matches, where you are confronted with 64 boards in 8 board segments (you compare with your expert but fallible teammates after each 8 board segment) are wonderful. Each segment is a mix of defence and declarer play. Two I recall as favourites: The Tough Game (it might be The Tough Match) and The Needle Match (it might be The Needle Game).

Back in the day I’d read these two before every tournament just to get myself thinking properly.

The bidding in these books is very dated, so sometimes the inferences drawn from the bidding may seem odd if you were to imagine current players bidding that way, but that’s a minor niggle.

I guess what I’m trying to say is that looking at hands you’ve played is unlikely, imo, to lead to improvement…you need to learn ‘how’ to think.

One truism, imo, is that the vast majority of defenders are blind to much of the information available to them. These books, and others like them, train one to pay attention and to THINK at a deeper level than you may currently be capable of doing.

[smerriman]

AL78, on 2022-July-12, 12:34, said:

Is it also worth looking at the boards where we got a good score?

If you are going to analyse your hands, you're definitely going to want to do this. All of your existing posts have proven pretty definitively that your score is often completely unrelated to how well you played (true in general, but even more so due to the high variance at other tables). As you can easily get a bad score for playing well, you'll also have a lot of hands where you made mistakes and got a good score.

[mycroft]

Lawrence's How to read your opponents' cards is a classic for a reason, and while it is POV declarer, a lot of the same analysis can be used on defence (obviously, you don't have the same control over the play as declarer, but what declarer is learning you can learn as well; as you can also use the play pattern of declarer to figure out what he's looking for - which can frequently tell you what he has).

[Douglas43]

Good point. There are many good books on defence at IMPS - Hugh Kelsey's Killing Defence and More Killing Defence spring to mind. But I can't think of any about defence at pairs. Can anyone recommend one?

At IMPS your objective is usually clear - "they are in 3NT, we want 5 tricks". But at pairs it isn't. Beating 3NT by one trick could score badly, while on the next board holding 3NT to 10 tricks is a top. A line which is the only chance at teams often blows a crucial overtrick at pairs.

My one tentative suggestion is; once you have seen dummy try to work out whether your goal is to beat the contract or just to get what tricks you can.

[mikeh]

Douglas43, on 2022-July-12, 22:25, said:

Good point. There are many good books on defence at IMPS - Hugh Kelsey's Killing Defence and More Killing Defence spring to mind. But I can't think of any about defence at pairs. Can anyone recommend one?

At IMPS your objective is usually clear - "they are in 3NT, we want 5 tricks". But at pairs it isn't. Beating 3NT by one trick could score badly, while on the next board holding 3NT to 10 tricks is a top. A line which is the only chance at teams often blows a crucial overtrick at pairs.

My one tentative suggestion is; once you have seen dummy try to work out whether your goal is to beat the contract or just to get what tricks you can.

I wouldn’t worry too much about the form of scoring used in any book on play. Yes, the goals are different between, say, mps and imps, but the skills needed to defend accurately are largely identical.

If I’m playing mps, then I will use the same skills to work out what’s going on, and what I can do about it, as at imps. My decision about what to do with the inferences I’ve drawn will be different…at imps, if I can imagine a lie of the cards that will let me beat a contract, I’ll probably take it even if it’s likely to cost an overtrick most of the time (when the cards do not in fact lie as I hope) while at mps I have to assess the likely cost of that overtrick, and my likely score if I settle for holding them. So there are factors beyond technical ability that influence one’s play. However, there’s no point learning about them if one hasn’t yet learned how to analyze the bidding and play.

[DavidKok]

AL78, on 2022-July-12, 13:13, said:

Thanks.

Do you have any recommendations for books on defence.

I guess with point 3, I could selectively post hands on here where I apparently had a choice of plays and chose the one that blew a trick, and see what others would have done at the critical time.

One big difference between forum posts and playing OTB is the timing. When you hand someone a bridge puzzle (or even if you casually ask 'what would you do here?') they will have advance warning that this moment requires focus and attention. At the table this is very much not the case, and usually defenders front load most of the hard mental labour. I think it is more instructive to ask "how would you plan the defence upon seeing the dummy?" than to ask "at this crucial moment, how do you not blow a trick?".

Personally I read a lot of bridge books (maybe 100 or so), most of them during Covid times. There are some books I strongly prefer to others for improving your defence. The two books I like best are "Killing Defense at bridge" by Hugh Kelsey (I wrote this before seeing that mikeh recommended it as well) and "Partnership Defense" by Kit Woolsey. I've read Kantar's "Defensive bridge play" and I do not like it, but everybody has their own preferred writing and learning style.
Another classic that will help indirectly is "How to read your opponents' cards" by Mike Lawrence - and I just saw that mycroft already recommended this one as well.

There are many more highly recommended books on all these topics (for example, on opening leads. Bird and Anthias have already been mentioned), and I've read quite a few of them, but in my opinion none of them come close to the above three for going from beginner/intermediate to advanced level of defensive play.

[P_Marlowe]

Defence is a partnership thing.

You need to get partner on board.
You seem to play often with partners lower in experience / strength than yours,
this means, try to find a set of defensive agreements, that robust and simple,
to get reliable information from them.

With kind regards
Marlowe