What's that??

[cherdano]

[hv=d=e&v=0&b=14&a=2s4np5np6cp6d]133|100[/hv]

 

4NT showed the minors. No other agreements.

[Fluffy]

I have only used pick a slam once (Wrongly) so not an expert. But IMO pick a slam is for chosing the right strain, even if north then bid 7♦ he would mean it as pick between 7♦ and 7♥ (which could be rectified to 7NT)

 

When willing to invite to grand one has 5♠ avaiblable.

[manudude03]

I would assume it would be a grand slam try without first round spade control (bid 5S instead of 5N with 1st round control)

[cherdano]

I would assume it would be a grand slam try without first round spade control (bid 5S instead of 5N with 1st round control)

That's how I meant option 2 - edited.

[kenrexford]

The meaning of 6D is in the difference between 5S and 5NT. If there are no general understandings, the nuance is impossible to work out.

 

To me, there are two reasonable interpretations. In one, you have a sort of flag approach, where 5NT was a slam try in one of the minors, apparently diamonds. In that interpretation, 6C must have been a sort of Last Train, 6D declining. Hence, 6D is a mild grand invite.

 

A second plusible is that the nuance is that one invites grand with control and the other without, in spades. In that event, 6C declined, and 6D corrected.

 

If 5NT asked for choice, I almost give up. But, if so, then 6D is a grand move. This suggests 5S as a club flag, 5NT as a diamond flag or choice. Not unreasonable, but not too smart to whip out undiscussed.

[PhantomSac]

Choice between hearts and diamonds

[gszes]

With no system in place I would assume the 5n followed by 6d was asking responder to bid a grand with 2 of the top 3 dia honors. A hand where advancer was willing to stop in 6d if overcaller chose 6d vs 6c (AKxx AKQ QJxxx A). This can be a useful treatment but hugely limited applications and only works for diamonds and even then only if partner chooses clubs vs diamonds (ie treating 5n as pick a slam see more below)*.

 

Responder has no room for fancy responses since it is quite possible advancer wants to play clubs. There are two suits where we might need a reasonable asking bid so we use 5s/5n do ask about the two suits. IHO (dont pull this on unsuspecting partner) 5s asks for 1st round control of spades while 5N asks for ONE of the top 3 heart honors. How else does advancer logically search for a grand with the following:

 

AKxx

AQJ advancer bids 5n asking for 1 of top 3 heart H

AKxxx

A

 

x

AKQJx advancer bids 5s asking for 1st round control of spades

AKxxxx

A

 

void

AQJxxxx advancer bid 5n asking for 1 of top 3 heart honors

AKxxx

A

 

A

KQJT9xxx advancer bids 5n asking for 1 of top 3 heart honors

AK

AK

 

x

AKxxxxx

AKxxx

void

 

*5n pick a slam is not useless but severely limited to essentially one hand type (something like) AK AKQJx Kxx Kxx) and wants responder to bid their best/longest minor to cut down on trump losers and has little to no chance of effectively searching for a grand (except when using it in conjunction with the 6c followed by 6d GSF interpretation).

[lycier]

6♦ says Grand slam try in diamonds without spade control.

If north have first control in ♠ with minors fit,it should start cuebid 5♠.

[Finch]

Am I allowed to know what 4NT meant?

In particular, did it show the minors, or was it any two-suiter? This is not at all obvious to me, because it depends on other agreements (such as NLM)

[lamford]

Am I allowed to know what 4NT meant?

In particular, did it show the minors, or was it any two-suiter? This is not at all obvious to me, because it depends on other agreements (such as NLM)

Unless the OP was changed between it appearing and your question, we should assume 4NT does show the minors. However, I don't think we are any further forward, as 5NT followed by 6D is undiscussed. Occam's Razor recommends the simplest explanation, and I agree with the brief response by PhantomSac that North has hearts and diamonds.