[uva72uva72]

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IMPs, ACBL robot individual

I'd like to suggest that 5-10 is too broad a range for North's 1NT bid. It should almost certainly be a constructive bid (8-10 or 9-11 would be my choice) and not a rescue. To my way of thinking, the odds were heavily tilted in favor of North holding the lower end of the range and that a raise to 2NT was likely to result in a substantial minus if so. Of course, North not only holds a max but a perfecto. It seems to me that the 5-10 range is overbroad and results in too much guesswork for South.

As for what North should bid in this sequence with 5-7, North has repeatedly demonstrated its fondness for 3-card suits, so it will have no problem coming up with another bid.

[iandayre]

Sources vary. I have seen as low as 5 with a double stopper - max is 9 or 10. GIB's range seems a bit wide but not that far from reality.

It's been well documented that I am no advanced mathematician, but isn't it true that within a given range, the more likely result is the one closer to the average point range, i. e. 10? So playing 15-17 notrumps, 15 is more common than 17, but in a response range like 6-9, 9 is more common than 6?