[frank0]

Just saw the post about whether to open 2♦ or 3♦ on a questionable hand. A few people mentioned the fact that we should be more careful at second seat.

Not saying this is not true. It's for sure that partner in average has more HCP after your RHO pass so your preemptive is less powerful. The thing I doubt is people include some bridge authors may overemphasize this factor a little bit.

I just did a quick and rough simulation by hand generator on web version BBO. I set the following condition

Hand 1~100("Second seat")
South 7♣, 0~4♦, 0~3♥, 0~3♠, 5~9HCP
East 0~11HCP
Hand 101~200("First seat")
Same for South, release the HCP restriction for East

I averaged North's HCP in each condition and got the following result,

Hand 1~100: 11.85
Hand 101~200:10.97

They are difference by less than 1 HCP, which makes me doubt whether we should worry too much about the difference between preempt at 1st or 2nd seat.

Any opinion or comment?

[Siegmund]

While it's true the average high-card expectation only goes up by ~1 HCP for third hand (and down by ~3HCP for first hand, after the pass), that means a lot of partscore hands -- and the death hands where partner has moderate values so that you will be down 1 in your preempt but opps cant make much -- remain in the pool, but a substantial number of game and slam hands for EW have been removed from the pool. If your preempts are relying on the assumption that your opps will always have a game if you are set, you are going to run foul of that assumption a lot more often in 2nd than in 1st.

The books do emphasize it more than they might need to for a careful and disciplined reader. In the real world, a great many people, even book readers, somehow remain oblivious to vulnerability and suit quality, let alone whether they are in 1st or 2nd seat, when it comes time to preempt.

[grishav]

The largest outcome of the preemptive bid comes from hands where:
a. opponents will fail to reach game/slam that they would reached without the preempt
b. opponents will overbid to game/slam which cannot be made
c. we will find good sacrifice against their game/slam
So the largest outcome comes from game or slam hands - not the partscores (shock! )
When one of the opponents passed, the chances that they can make a game (not to talk about slam) are definitely smaller, and therefore the preempt is less effective.
It's not only the question of partner's HCP - though it's also one of the factors we should consider.
I think that the other factors are:
1. LHO knows that his partner is limited in strength. After his partner's pass, he will know (sometimes) that they cannot make a game, so he will overbid less frequently.
2. If there are two strong hands on this board, they will be partner's and LHO's. So finesses they need for their game or slam will lose more often. Moreover, LHO knows this after your preemptive bid - so he will proceed with more caution and will make the right decision more frequently.
3. If they play penalty doubles after preempts (though it's not too common nowadays I admit), it will be easier for LHO to double you knowing that they probably can't make a game.

Though I don't know how to include these factors in your model, I think they affect the outcome of preemptive bid and therefore your model is not complete.

[ggwhiz]

Using HCP's cannot be accurate when the more extreme distribution of a pre-empt tends to be duplicated around the table.

As pointed out, the odds of jobbing the opps out of a contract are much less after the first pass and the odds of jobbing pard out of our best spot increase, ie. pard is short in our pre-empt suit with a mediocre 5-card major that we can support.

It only takes one such 2nd seat misadventure to raise partners blood pressure and have them guessing into the future.

[Free]

Many people open 11 counts.

[Cthulhu D]

How much do the odds change with 11 point hands and any hand with a 6 card suit (the sort of thing that might have attracted a weak 2 opening) in the 1st seat change the possibilities for north?

[the_dude]

frank0, on 2012-January-04, 22:42, said:

Just saw the post about whether to open 2♦ or 3♦ on a questionable hand. A few people mentioned the fact that we should be more careful at second seat.

HCP isn't that relevant .. the issue is a little deeper than that.

Remember preempting is essentially accelerating the auction, giving less room for accurate hand description. Second seat is important because it presents least opportunity to disrupt the opponents communications and the greatest opportunity to disrupt your own.

When you preempt in first seat, you may be trip up your partner, but you are also tripping up TWO opponents. But in second seat, your RHO has already communicated SIGNIFICANT information to his partner by virtue of his pass. Accelerating the auction now often does just as much damage to your partner as it does to the opponents.

This is especially important if one of the hands is big enough to put game in the picture opposite a noon-opener .. and at this point it's 50% likely that your partner holds the big hand.

You can mitigate this by being disciplined in your second seat preempts (meaning strictly adhering to your partnership standards, whatever they may be). That way at least if your partner has the big hand, he knows what you have and can act accordingly.

[Lurpoa]

Free, on 2012-January-06, 00:22, said:

Many people open 11 counts.

♥♥♥

Oh, Oh,

but that is a crime !

♥♥♥

[32519]

the_dude, on 2012-January-06, 15:59, said:

HCP isn't that relevant .. the issue is a little deeper than that.

Remember preempting is essentially accelerating the auction, giving less room for accurate hand description. Second seat is important because it presents least opportunity to disrupt the opponents communications and the greatest opportunity to disrupt your own.

When you preempt in first seat, you may be trip up your partner, but you are also tripping up TWO opponents. But in second seat, your RHO has already communicated SIGNIFICANT information to his partner by virtue of his pass. Accelerating the auction now often does just as much damage to your partner as it does to the opponents.

This is especially important if one of the hands is big enough to put game in the picture opposite a noon-opener .. and at this point it's 50% likely that your partner holds the big hand.

You can mitigate this by being disciplined in your second seat preempts (meaning strictly adhering to your partnership standards, whatever they may be). That way at least if your partner has the big hand, he knows what you have and can act accordingly.

I find this thread fascinating read alongside awm’s thread, “Shape First!” http://www.bridgebas...14-shape-first/ Here are just two extracts from awm’s thread:
• Looking at the CCs of Bermuda bowl pairs, you see a lot of wildly different stuff. That's one of the great things about bridge. But one thing that seems almost universal in bidding trends is that showing shape early is good.
• I like most auctions to emphasize shape and not high cards though, since shape is really what’s important.


Both threads contain convincing arguments when to bid (2nd seat pre-empt versus showing your shape). The range of shape showing bids in any partnership is limited by your own imagination (and partnership agreements). Some popular shapely bids which immediately come to mind are:
• Muiderberg
• Multi 2NT showing 5-5 minors
• Canape

Whose advice is better here? Think twice before pre-empting in 2nd seat? Or get into the auction and show your shape?