Presumptive Fit Preempts .. Jammer 2D

[BridgeBuff]

it occurs to me that the calculations on 'lawfulness' might not have taken this into account? -- so the figure of 70% may be an overestimate?

 

Yes the calculations of the (ABCD) components in this thread reflect rules that responder would use. Using Short Club Jammer, on a scramble, one of those rules would be ‘holding equal-length majors, bid hearts’ so responder with 4=4=2=3 opposite opener with 5=3=4=1 would land in 2H oops. That hand combination would be in the ‘B’ category and the 70% lawfulness is accurate that way.

 

(You might decide to use a rule that says bid 2S with equal-length majors for pre-emptive reasons)

 

Any system has ‘oops’ bids. The two-suiter bids have better precision for the two suits, but more ‘oops’ bids overall. Rough Diamond has 40% ‘oops’ positions compared to 30% Jammer, so you have to look at the bigger picture.

 

You’re right about safety versus lawfulness. One system might be less lawful but safer but that would have to be tested at the table for some period of time. Certainly a 10% difference in lawfulness is a huge difference to make up and Jammer might very well be ‘safer’ as well because it is not so well defined. As well, the Jammer bid frees up 2H for another purpose.

 

That two-suited Frelling 2S bid looks very reckless to me, but to each his own.

 

Yes that response system is sensible. With a weak hand you just scramble. For invitational+, you could build a sensible response system starting with 2N. Maybe 3C would then show a minimum hand not both majors (3 of one of them), 3D minimum both majors, 3H maximum both majors, 3S maximum with 4+ spades, 3N maximum with hearts .. or ???

 

Strong responder with 4=4=2=3 opposite opener with 5=3=4=1 would find his spade fit with:

 

2D

2N query

 

3C minimum one major

3D which major?

 

3S

pass or 4S

 

There might be more clever response systems ….