[alpine]

Here is the hand:
N： S:AQXXXX H:AXXX D:KX C：K
S： S:X H:KQXXXX D:QX C：AQXX
S W N E
1H P 1S P
2H P 4C① P
5C② P 5D③ DBL
P P 5H④ p
p⑤ p p


① 4C means splinter. Which one is the best ? A.2D B.4C C.4NT
② 5C cue bid. Which one is the best ? A.4H B.4S C.4NT D.5C
③ 5D cue bid. Which one is the best ? A.5D B.5H C.6H
④ 5H. Which one is the best ? A.5H B.6H
⑤ PASS. Which one is the best ? A.PASS B.6H C.5S

Which one should be responsible for losing the slam? N or S

[SteveMoe]

Not particularly fond of splintering with a singleton A or K. Makes slam evaluation more difficult.
Would try something like:
1♥ - 2N (Jacoby)
3♠(singleton)-4♦(control/slam interest/extras)
4N - 5♥ (2 keys w/o Q)
6♥

Those uncomfortable raising ♥ holding 6 ♠ cards might use:
1♥ - 1♠
2♥ - 3♦ (3rd suit forcing)
4♣ - 4♠
4N - 5♥
6♥
Here 4♣ patterns out showing 6=4 in a weaker hand.

[johnu]

Sorry, I don't have a sequence for a 6=5=2=1 hand opposite a 1=5=2=4 hand.

[alpine]

sorry,I gave the wrong hand.Now i modified:

N： S:AQXXXX H:AXXX D:KX C：K
S： S:X H:KQXXXX D:QX C：AQXX

[ggwhiz]

I strongly favor 2nt instead of 1♠. After a 3♠ response you could bid 4nt right now. It's an unlikely parlay for you to be off on a diamond lead (when pard has xx) AND for them to find it.

By agreement when we respond to 2nt we treat stiff Ace and King as doubletons and we don't splinter with them either in line with Steves thoughts above.

[EricK]

Although I don't agree with many of the bids chosen, I think north is 100% to blame for missing the slam. If I picked up that hand and heard partner open 1[H] then my thoughts would be more along the lines of "7 or 6?" rather than "game or slam?".

[lowerline]

I prefer to support hearts immediately. Then the choice is between Splinter and Jacoby 2nt. I would choose Jacoby.

1♥-2nt
3♠-4♣(1)
4♥-4nt
5♠-6♥


(1) should show serious slam interest (otherwise 3nt)

Steven

[Cyberyeti]

Show your fit first, are you ever going to want to play in spades after partner opens hearts ?

Our auction (we play strong jump shifts either one suited rock crusher or HHxxx in the bid suit and Hxxx in opener's H=AKQ)

1♥-2♠
2N(small singleton spade or less)-3♣(fit type, cue)
3♥(waiting, no diamond cue)-3♠(ace)
4♣-4♦ (both cues)
4♠(kickback)-5♦(2 without Q)
6♥

In your auction, when E doubles 5♦, N suspects ♦AQ sitting over his K, it's up to S to bid the slam, but it's not easy, could be KJ10 behind the A and another loser.

[Zelandakh]

As others have pointd out, one way of simplifying the auction is to make an immediate GF raise. The alternative is for South to make a sensible rebid (2♣) and then North shows slam interest via 4th suit forcing and bidding hearts. After that it should be relatively easy.

[jfnrl]

French Standard 5M :

1H 1S
2C 3H
4C 4NT
5S 6H


1S : no direct raise with 4 cards and GF
2C : 2H would show one-suited hand
3H : slamish (Qxx minimum in H)
4C : C stopper (A or K), promise decent H (minimum KJxxx) and a no-minimal hand, singleton S is not to bid as it is in partner's suit.
5S : 2 aces (from 5) and HQ
6H an ace is missing