benlessard, on 2012-February-22, 09:30, said:
http://www.blakjak.d...k/def_1nt31.htm
2C = 5C+4M or 5C+4/5D
2D = 5/6D+4M
2M natural.
X show a 5M + another suit. This is superior to Vertigo since my bids are slightly more preemptive and less vulnerable to preemption.
Zelandakh, on 2012-February-22, 09:46, said:
Agree absolutely that 2M should be single meaning natural, and agree absolutely that it is important to know which of 2 suits is longer. This is a big problem with most of the defences showing a major and a minor, which could be 45 any way round. As partner, if it can be a 5 card major I may want to be in that, but if it is a 4 card major, then want to be in the minor.
A practical problem with defences where a minor shows a specific major is that you cannot pass the minor as it may be the wrong one. In effect you have to go to the 3 level. I think it more sound that a minor bid shows that minor and an unknown major. With length in the minor you can pass it.
This is why I play vertigo, and like it.
Most of my opponents play weak NT, but I am still happy to give up the penalty double. Without the double (you have to pass with a strong balanced hand) declarer will not know you have such a strong hand and possibly not play so effectively, and having no penalty double means that they cannot escape to responder's 2 of a minor or weak 2 suited hands. (Of course, should partner reopen with a vertigo double then you have the option of passing.)
With one partner I play vertigo where the double is either a 4 card major and a 5 card minor or both majors any length. With another partner I give up the 5m4M hands and have double as just both majors. Then you can always play in the best fitting 2M regardless of length (eg partner bids his longer major, but with equal length he bids 2♦ for doubler to bid the longer), and you can also have the option to play a response of 2♣ as pass or correct to 2♦ if partner hates both majors.