thepossum, on 2021-September-09, 04:02, said:
I would be grateful on any advice how to evaluate that though, including how to rule out options from partner's pass
2
♠ is weak, and 4
♠ is almost certainly pre-emptively bidding to the level of the fit given your strength.
They are likely to have a 10 card fit and partner is unlikely to hold any wasted values in spades. This means wherever partner's values are (if any), they will be in hearts or clubs (you hold all the diamond honors), in other words complementing your honor cards. It is a 30 point pack situation.
Give opener 7-8 HCP, combined with your 18 count gives 25-26 HCP between you and opener. That leaves around 14-15 HCP between the other two hands. Give partner 6-8 of those in hearts and clubs. How many ways can you give partner a couple of club/heart honor cards and not have play for 5
♦, bearing in mind you just need him to cover two of your four losers? The answer to this question will tell you that bidding 5
♦ is a decent shot.
In in the unusual case of partner being completely broke, you might not be defeating 4
♠ on a handful of possible layouts.
I don't like the idea of bidding 4NT. The disparity between the minors is too large, and if partner has more clubs than diamonds, you may still want to play in diamonds. There is one danger if partner has long clubs to the queen and short diamonds, if you are in 5
♦ missing the club ace, the defence will go club to the ace, club ruff, cash spade winner, down one, when 5
♣ makes, but that would be unlucky.
I rank ....
1, Double = T/O. 4 tricks might be easier than 11. Partner can show a good suit or 2 suits (4N)..
2. 5♦ = NAT.
3. Pass = NAT. Timid with 3.5 quick tricks and a good suit.
4. 4N = UNT. But you are likely to reach a 4-3 ♣ fit..