lamford, on 2017-February-07, 05:03, said:
South's hesitation implies doubt.
He is less likely to hold 25-27 balanced.
He is likely to be stretching with a sub-minimum or underbidding with a super-maximum (e.g. 28 HCP). He'll pass 4N with 24 HCP, bid 6N with 28 HCP.
- If South holds 26 or a good 25 HCP, then many would prefer to stay out of 6N with a combined 30-31 HCP. The hesitation makes these holdings less likely.
- If South holds 24 HCP. then 4N should be OK with a combined 29 HCP. Of course, if South goes one down, then you'll regret that decision.
- If South holds a good 27 or 28 HCP, then 6N on a combined 32-33 HCP is likely to be an acceptable contract,
Hence, the UI makes a quantitative 4N safer.
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