straube, on 2014-February-24, 16:18, said:
I think it's nice for double to leave the option open for conversion, so double would show less direction than 3S.
Is it harder to convert a double showing 4+ spades than one showing either 4 spades or a hand without a stop? I do not really know which would have the more successful conversion rate here. To the end of making this decision easier though, if we were really feeling frisky we might try: X = stopper ask (but not denying a stopper); 3
♠ = 5 spades; 3NT = 4 spades, with Opener showing whether they have a stop or not via 3
♠/3NT over the double. At the end of the day, once we make the auction GF we have essentially 4 hand types and 3 calls, so double takes two of the possibilities and 3
♠ and 3NT one each. We just need to decide which two hand types make for the most profitably conversion decisions (and not forget if 3NT becomes artificial!).