[P_Marlowe]

Hi,

the setting: you are playing with your son (10y) at the monthly F2F gathering of your club,
a small Team match, the main goal is social, and having fun.

System in place is 5 card major, with 15-17NT, 1D opening could be 3.

You hold in 3rd position at equal vul.

♠ -
♥ K98x
♦ Q987x
♣ AQTx

The bidding starts

1D - (1S) - X - (4S)
Pass - (pass) - ??? (1)

(1) your bid? If you want to go scientific, I will try to give responses to your possible bids,
but try to remember the setting, and the part of the forum I have posted (mainly due to the setting).

With kind regards
Marlowe

[DavidKok]

I do not like the double last round.

Given the forum, there is not much you can do. Either bid 5♦ or bid 6♦. Do you feel lucky? I think 6♦ is a slight favourite, but perhaps the social aspect is decisive and your son would not appreciate the pressure of declaring a slam.

[P_Marlowe]

 DavidKok, on 2024-October-21, 04:07, said:

I do not like the double last round.
<snip>

I think elaborating, why you dont like the neg. X may be helpful to the
forum audience, I did not give it much thought either, I am willing to
show the support regardless of level I have to.

[DavidKok]

When partner opens 1♦, it is very unlikely he has a 5(+)cM (and even if he does, we have an 11(+)-card diamond fit, which should play well). Therefore, opposite our spade void, the opponents most likely have a 9(+)-card spade fit, and potentially a longer fit.
While 1♦ can be a 3-card suit, it most often isn't. I do not know whether your agreement is "can only be 3 if 4=4=3=2", "better minor" or something else, but either way the chance of opener having exactly three diamonds is low. Even conditioning on our own hand and the overcall, I estimate the chance that partner has exactly 3 diamonds to be in the 10-20% range.
Combining the above, I think the total trumps on this deal are most likely 18+, and on average I think 19 is more likely. This means that we should anticipate having to take 5-over-4 decisions.
For competitive purposes, us having diamonds and hearts is equal when fighting against their spade fit. Either way we will have to go to a higher level to compete with their boss suit, and either way they do not have a spare strain in between (which would be the case if we had clubs and hearts). This means that, conditional on us having a heart fit, there is not much competitive benefit from playing in hearts over diamonds.
Since this is a teams match, there is also not much score benefit to playing in hearts compared to diamonds. The main scenario where this matters is if the opponents subside in 3♠ and we can play 4♥ or 4♦. But if partner has hearts we have a double fit, which increases the total tricks on this deal and with it the chance that the opponents will bid 4♠ over our 4-level contract. I think this is too narrow a target to cater to.
Conversely, supporting the diamonds right away gains every time partner does not have a heart fit, and some of the time when partner does. Our diamonds are longer than the hearts and I think a diamond fit rates to play better than a heart fit. This helps partner evaluate their hand right away.

Combining the above, I think our hand is best described as "a game forcing diamond raise with short spades" as opposed to "a hand with 4 hearts and diamond support". I would bid 4♠ or 3♠ immediately.

[P_Marlowe]

Hi,

I think 5D is sensible, and would have been my choice, if faced with it, but this was the seq.
on the other table.

At my table, the auction went different, there was only a single raise, and opener was able to
show his 4 card heart suit, i.e. the seq. was

1D - (1S) - X - (2S)
3H - (pass) - ???

my guess is, that if one thinks, that 6D is odds on to make, the known double fit did not make the
odds worse.
If you go for slam, do you go for hearts or for diamonds. You also can bail out and bid 4H.

With kind regards
Marlowe

[jillybean]

DavidKok, on 2024-October-21, 05:37, said:

Combining the above, I think our hand is best described as "a game forcing diamond raise with short spades" as opposed to "a hand with 4 hearts and diamond support". I would bid 4♠ or 3♠ immediately.

I appreciate comments, we have found our ♦fit! In a non competitive auction we have time to go slow and check to see if we have a double fit in the red suits, but not here.

5♦ it is, I think you risk being left to play in ♠ if you bid them.
♠ is a safe bid in the I/A forum.

[P_Marlowe]

jillybean, on 2024-October-22, 06:00, said:

I appreciate comments, we have found our ♦fit! In a non competitive auction we have time to go slow and check to see if we have a double fit in the red suits, but not here.

5♦ it is, I think you risk being left to play in ♠ if you bid them.
♠ is a safe bid in the I/A forum.

He would have told you, that it is a splinter. This does not mean, that the bid, he would have choosen in response to the 4S bid, would have made you any wiser, he would have likely bid 5D.

The main problem with the 4S bid: you are looking at the 1st round club control, and there is not much room between 4S and the safe haven 5D.
Going slow allowes the opponents to exchange information, but it also gives you the time / option to listen to the opponents.
Sometimes they tell you something worthwhile, sometimes not.
With the 1S - 4S auction, you can be pretty certain that at least 8 of the 10HCP in spades are with the opponents.