Post by ***@verizon.netIn contrast, after the auction 1D - 3D ; ? opener will feel sure that
the diamonds won't run, and will NEVER permit a 3NT contract. Or do
ANY of you weak notrumpers have a rebid for opener that demands 3NT
with 2 top diamond honors. Congratulations on your planning. Has it
ever come up at the table?
Many systems (perhaps even most serious systems) have a response of this
nature for responder over opener's weak NT. Giving opener a similar
bid would be interesting, but once the bidding's already reached an
inverted 3D it's hard to be that specific (you don't normally want to
force your side to 4). That said, opener can be aware of a 9-card fit
in that situation, and those have a decent tendency to run, so opener
will be open to the potential of 3D based on a running suit. (In
particular, when you have a particularly long fit, your partner is much
more likely than your opponents to hold missing honours in the suit.)
I think the most commonly seen convention in this situation is the
"Grant hack": after 1D...3D, 3H shows a hand that wants to play in 3NT
but isn't sure. Responder can reply with 3S or 3NT to play 3NT from
opener's or responder's side respectively (based on deductions about
where the stoppers are), or 4D to reject the invite.
In the case where responder /does/ have two top diamond honours, it
should be obvious what the opener was asking about, allowing the
responder to accept. The main problem is that in the case where
responder doesn't, they'll have to guess what prompted the invite, and
they may accept it if, say, they have two suits unexpectedly stopped.
(That said, 3NT in that situation might end up making anyway even if the
diamonds don't run.)
--
ais523