[Dadeliva]

2NT probably fails so often because declarer has to play mostly out his hand and has few opportunities to take finesses.

An interesting convention in MP's would be to "Trouble" DBL in 4th hand on most hands regardless of point count since you will get a top 60% and a zero in 40% of the times so on average a 60% score!!
If you include the requirement of having an honour in each suit or at least 2 filled 4-card suits (like J109x or Q109x) then the chances of declarer going down increase.
This because partner is less likely to blow a trick on the lead or suits won't run for declarer.

You will have to alert this since it is an unusual agreement. Partner of the opener could trap-pass if you double on any hand, but this is to risky if you include some requirements.
At IMPS it will cost to much if they make it. Maybe then it is profitable if you play that is promises 2 badly breaking suits.

Daniel de Lind van Wijngaarden

[AL78]

 Vampyr, on 2012-March-26, 09:53, said:

Come on, Robin, there are some!

Indeed there are. The system alone does not define a player's ability.

[helene_t]

 han, on 2012-March-26, 08:01, said:

Quote

85% of 7NT contracts are made

It seems to me that an easy solution is available.

The following really happened at a hospital staff bridge club in Amsterdam:

1NT-p-3NT-a.p.

Dummy tabled a 0 count.

Declarer: why did you bid with that hand?

Dummy: My teacher taught me that 1NT is the most difficult contract to make and that 3NT is much easier.