[Cascade]

I thought I knew what was standard in the following situation but yesterday I had a disagreement with a partner.

1♠ (2♥) Pass (Pass)
2♠ ...

What is the minimum requirement for 2♠ here?

What is the strongest hand you would bid 2♠ on?

What is the minimum or a jump to 3♠?

Are there similar hands that would double first and then rebid spades?

[steve2005]

There are certainly has that would double and then bid spades.
Any hand with 0-2 spades potentially would be a candidate as the best hands partner can have will have hearts. Doubling caters to this.
The range of strength to double and bid will depend on many variables.

[nige1]

Cascade, on 2017-September-09, 20:33, said:

I thought I knew what was standard in the following situation but yesterday I had a disagreement with a partner.
1♠ (2♥) Pass (Pass)
2♠ ...
What is the minimum requirement for 2♠ here?
What is the strongest hand you would bid 2♠ on?
What is the minimum or a jump to 3♠?
Are there similar hands that would double first and then rebid spades?

It depends on partnership agreement. In many partnerships, opener must call again if short in the overcall-suit.
If responder passed with values, then those values are likely to be the overcall-suit.
Hence, opener should re-open with a double, if possible, rather than bid a suit.
Responder should allow for the possibility of off-shape doubles e.g.
♠ A x x x x x ♥ x ♦ A K x x ♣ x x
Sometimes, however, opener will have little defence or shortage in an unbid suit.
A void in opponent's suit also reduces defensive suitability.
In Cascade's auction, declarer might rebid 2♠ with as little as
♠ K Q J x x x ♥- ♦ x x ♣ Q J x x x
Opener might rebid 2♠ with a stronger hand e.g.
♠ A K Q J x x ♥ x ♦ Q J ♣ x x x x
For a 3♠ rebid, opener needs a good suit e.g.
♠ A Q J x x x x ♥ x ♦ K Q ♣ x x x
But players' judgements vary and different partnerships will have different agreements for all these calls.

[The_Badger]

I will ask the question another way: What's the minimum for partner to make a negative double on this auction?
It's sometimes assumed that partner has passed as he's holding the opponent's suit when in reality he's just got a poor hand. A 2♥ overcaller on this auction could have 15+, especially vulnerable, preferring an overcall to double and bidding his suit, or being totally barraged out of the auction by a pre-emptive raise of 3♠ from opener's partner.

Nige1 makes some good points, as always, but as he says this scenario, especially this ♠s vs. ♥s auction where there's less space to operate, is for partnership agreement.

[Cascade]

nige1, on 2017-September-09, 21:27, said:

It depends on partnership agreement. In many partnerships, opener must call again if short in the overcall-suit.
If responder passed with values, then those values are likely to be the overcall-suit.
Hence, opener should re-open with a double, if possible, rather than bid a suit.
Responder should allow for the possibility of off-shape doubles e.g.
♠ A x x x x x ♥ x ♦ A K x x ♣ x x
Sometimes, however, opener will have little defence or shortage in an unbid suit.
A void in opponent's suit also reduces defensive suitability.
In Cascade's auction, declarer might rebid 2♠ with as little as
♠ K Q J x x x ♥- ♦ x x ♣ Q J x x x
Opener might rebid 2♠ with a stronger hand e.g.
♠ A K Q J x x ♥ x ♦ Q J ♣ x x x x
For a 3♠ rebid, opener needs a good suit e.g.
♠ A Q J x x x x ♥ x ♦ K Q ♣ x x x
But players' judgements vary and different partnerships will have different agreements for all these calls.

Are these the strongest hands for 2♠?

What do you do with 16-18 points?

The 3♠ example that you gave seems to need a lot for game opposite a passing partner who could be weak.

I would bid 3♠ on a hand that just needs a trick or two and a perhaps a bit of luck to make game. The six loser hand you show seems quite weak since I think you will probably induce 3NT when partner has moderate values and a heart stopper with no spade fit.

Your strong hand with ♦ QJ only does not seem that strong. I would comfortably bid only 2♠ with ♦KQ or ♦Ax and even a little more.

[Fluffy]

2 spades promises a side singleton (not in hearts)

2 spades could be a bad 17 hand at most

3 spades should be rare, a really high ODR hand.

[Cascade]

Fluffy, on 2017-September-11, 05:10, said:

2 spades promises a side singleton (not in hearts)

2 spades could be a bad 17 hand at most

3 spades should be rare, a really high ODR hand.

Definitely with a singleton not in hearts you would bid. However I think there are problems with hands that do not have a singleton not in hearts. The frequent problem is when partner pulls a double to 3m and now you do not know whether to rebid your spades. Compare

1♠ 2♥ Pass Pass
Dbl Pass 3♣ Pass
?

1♠ 2♥ Pass Pass
2♠ Pass 3♣ Pass
?

On the second auction you are much happier passing. The more often we double maybe the more often we will extract a penalty but also the more often we will be guessing a round later.

[aguahombre]

My policy is to only rebid 2♠ when it is wrong.

[Winstonm]

Seems to me the two possibilities for 2S woud be either A) a hand strongly aligned toward offense or B) a hand too powerful to pass but with length in the overcalled suit. I would think all other hands would fall into the reopening double or pass categories.

As to top end, I would imagine playing strength more than anything else would determine the separation between 2 and 3. I would think a hand that reopens with 3S should have close to 9 tricks in hand - maybe a solid 8 or 8 1/2 trick hand. 3-card support, an odd king or even queen, and a ruffing value could be enough for to consider a raise to game by the passed hand.

[nige1]

Cascade, on 2017-September-10, 16:51, said:

Are these the strongest hands for 2♠?
What do you do with 16-18 points?
The 3♠ example that you gave seems to need a lot for game opposite a passing partner who could be weak.
I would bid 3♠ on a hand that just needs a trick or two and a perhaps a bit of luck to make game. The six loser hand you show seems quite weak since I think you will probably induce 3NT when partner has moderate values and a heart stopper with no spade fit.
Your strong hand with ♦ QJ only does not seem that strong. I would comfortably bid only 2♠ with ♦KQ or ♦Ax and even a little more.

You and Fluffy have persuaded me that my 4th example hand falls far short of a 3♠ rebid.