delmo

Already explained in the text. Please read once more.

Forget about the off-shape (since you did not know it when it was opened). Just count your partner for 20-21 HCPs. With your 13 HCPs, you don't have enough for a grand slam, but more than what is necessary for a small slam, go straight to 6NT without any further ado.

Why “under-leading the K” is such a taboo? The other day, we encountered a hand as shown. Every pair in the field made 6 or 7, but nobody else made a Slam bid, except our pair with some possible overbidding on the part of my partner or a misunderstanding on my part. As mutual understanding, a response of 2/1 is meant to have 12+pts with 10+HCPs. So, my landing on 6♥ was based on my expecting partner to hold either the K of ♠ or the Q of ♥ with some distributional points. But as the cards lie, I realized that my partner had either over-counted the J of ♥ for 2 HCPs in support of my 1♥ opening, or assigned an extra point to the forth ♥. It’s clear that an opening lead of ♠ will beat the contract. But nobody made such a lead. For me, the opening lead was a ♦, and I made my small slam with an extra trick for a score of 1010 points and 11 IMPs. [hv=pc=n&s=sj64hak542dajca52&w=sk9873hqtd974cj76&n=st5hj873dkq852ck8&e=saq2h96dt63cqt943&d=n&v=0&b=1&a=pp1hp2cp3np4hp4np5cp6hppp]399|300[/hv]

As South, your holding and the bidding are as shown. What is your last call? [hv=pc=n&s=skhaq98daq3ca7532&d=n&v=n&b=5&a=1sp2cp3cp4np5sp]133|200[/hv]

North’s opening lead was the A of Clubs. He then shifted to the 9 of Hearts, probably asking for a shift to a higher suit? I, as South, took with the A, then shift to a Diamond, which North ruffed for a result of 11 IMPs for our side. Note that EW could make 5D, but not 5S, while NS’ 5H was cold. [hv=pc=n&s=s85hat84d87642c62&w=sa7432h3da95cqjt3&n=s9hkq97652dca9874&e=skqjt6hjdkqjt3ck5&d=w&v=n&b=12&a=1s2s3h4hpp4s5hpp5sdppp]399|300[/hv]

I agree with this comment. Yes, it's West who should bid 4NT, since E already showed an opening value by doubling the 3♥ bidding by N.

Thanks all for good advices.

Thanks to Cyberyeti and others for good advices

Thanks Wank for showing the whole board. Yes, I bade 5♦, doubled, but got 4+ IMPs. I could alternatively bid 5♣ for the same reason. There was 16 pairs to have played the board, and 5 pairs had chosen the same decision as mine. My decision was as follows. Since N already showed 7+♥, and S, presumably, also 7+♠, I had 3♠, then my partner should be very short in ♠, and at the same time, he should be very long in both ♦ and ♣.

[hv=pc=n&e=s532h87dakq9ckj76&d=n&v=0&b=1&a=3hd4spp]133|200[/hv] As East, the bidding has gone as shown. What will you bid now?