Balanced 15-count again

Above is the West hand opposite our 1NT opening.

1NT12-15 balanced-ish, no 4cM
2C3C3-3-4-3
3D4C10 SPs (A=3, K=2, Q=1)
?

3D risked hearing 4C. Otherwise West would play 3NT.

Is 10 SPs enough? The opponents have 4 SPs, so K-K or A-Q.

The CQ will be crucial. Hope we can stop somewhere (5NT) if partner lacks that card.

4D4HD = 0 or 2 including Ace, so A-K or A-Q
4S5CS = yes, H = no

That was a bit lucky. No heart honour means partner must have

Axx, xxx, AKQx, Qxx

Therefore 6NT. Nice DJ we had!

Note that’s a 15-count. Some of the strong notrumpers got to slam over that minimum. We needed to work harder because that is a maximum.

Say partner had bid 4NT = 0 or 2 spades honours. If zero, then

xxx, KQx, AKQx, Qxx.

Then West bids 6C to protect the spade king. What if partner has S-AQx?

That’s not so good. 8 or 9 SPs in those suits means 1 or 2 in the other two, maybe no CQ.

AQx, Qxx, AKxx, xxx. Or maybe AQx, Kxx, AQxx, xxx

Now slam is odds against opposite those 15-counts. Partner could have the CQ:

AQx, xxx, AKxx, Qxx, when slam is quite good.

All in all, still worth it. Can we stop in 5NT opposite that wrong hand? Let’s see

4S4NTS = 0 or 2
5C5HH = yes, C =no
5NT

Never fun to play 5NT. Opposite AQx, Kxx, AQxx, xxx, it looks to be about 70% while 6C is about 35%. Who has time to work that out?