[lycier]

Experimental investigation of the Gib rebid issue.
- This never be a occassional small issue of one hand.
- This is one of the serious problems associated with TPs.

First, see my traveller.



Second, here are two classic hand.
Hand-1

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Result : 2♦W+4

Hand-2

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Result: 3♦W+2

Third, let's discuss its rebid issues.
- See hand-1
1nt says " 8-11hcp,likely stop in ♠ ". Ok, this is a perfect explanation, very good.
However the peoblem is from the explanation on Gib opening suit rebid, 2♦ says " Good suit --- 11-21hcp,biddabe D,12-22 TPs." ! Too wide TPs range, and 2♦ doesn't show forcing bid, so it is very reasonable for east to pass.
Such TPs definitions are too fuzzy and too wide range.
What's the strong? What's the super strong? How to distinguish with each other? I think Gib CC can't resolve this serious issue.
I think here are its ranges in detail.
Strong hand= 15-18 TPs, invitational.
Supper strong hand= 19+TPs
Even my English is poor, my wording is poor, Gib usually does not distinguish with them in fact.

Maybe you can't believe what I said, now here are my evidence hands.
Hand-3

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We can see that 16TPs(3♦=16-19TPs) plus east 8TPs equals to 24 TPs, so east think it is not strong enough to force to game, eventually pass.

Hand-4

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We can see 12TPs(4♦=12-22TPs) plus east 8TPs equals to 20TPs, so east pass.

Hand-5

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We can see Gib regard 17+TPs as a forcing bid since 17+8=25TPs.

- See hand-2
3♦ says " twice rebiddable D,15-22TPs.", east think 15+8TPs=23 TPs, less than game 25TPs, so pass after rebid-3♦.

Fourth, my suggestions :

Of important, Gib should distinguish different ranges with 12-14 TPs,15-18TPs and 19+TPs so as to avoid unnecessary guess.

Welcome everyone and experts especially Stephen Tu to point out my wrong, and thank you very much.

This post has been edited by lycier: 2016-May-29, 01:26

[Stephen Tu]

I agree that GIB's bid choices and the range definitions currently used for these auctions presented are really bad and should be adjusted to be much narrower and lower, to prevent GIB from underbidding. Possibly the rule for bidding 1nt as East should be slightly tighter too, 8-10 instead of 8-11.

I disagree that the problem is "associated with TP". You keep on trying to blame the use of TP when it is just the bad range definitions of bids or bid priorities that are to blame. Adjust the TP ranges in the definitions, define the rule for bidding 3nt such that this hand is included, and the problems go away.

[lycier]

Stephen Tu, on 2016-May-29, 08:08, said:

I agree that GIB's bid choices and the range definitions currently used for these auctions presented are really bad and should be adjusted to be much narrower and lower, to prevent GIB from underbidding. Possibly the rule for bidding 1nt as East should be slightly tighter too, 8-10 instead of 8-11.

I disagree that the problem is "associated with TP". You keep on trying to blame the use of TP when it is just the bad range definitions of bids or bid priorities that are to blame. Adjust the TP ranges in the definitions, define the rule for bidding 3nt such that this hand is included, and the problems go away.

Thank you very much for your good reply, I can accept your opinions.