Following a few recent IMP shocks I've been analysing all sequences in a group of tables with the same hands to find out why some sequences have such massively divergent outcomes despite going via a bid with the exact same description and strength
I do not know if the issue is one of understanding the complexity/precision of certain sequences in 2/1 or how GiB has coded them. However it is clear that when bidding you cannot rely solely on bid descriptions and need to bid according to system rather than how GiB describes them
In a recent hand which makes 7D or 7NT many souths were left in 3NT and many received a jump to 6D by GiB after south's 3NT despite the description on the 3NT being identical in all the sequences.
The issue comes down to earlier bids in auctions
If you have the following sequences. North (GiB) opening the bidding, no interference EW
1. 1D-1S-2D-3N-?
2. 1D-1S-2D-3C-3D-3N-?
3. 1D-1S-2D-2H-2N-3N-?
The 3NT by south is described identically in each auction. However the first two resulted in a jump to 6D and the third resulted in a pass
North (GiB) had the following hand
What I am curious about from both a 2/1 and GiB perspective is why sequences 1 and 2 are so different to sequence 3
regards P