Came across this hand in a tournament. both vulnerable. East is dealer and astonishingly opened 2 diamonds - which they confirmed was a preemptive 2 bid. What should south bid? A straight 2 spades is acceptable but does not give information on true length and does not give information on the power of the hand. A Double implies more high card points.
Our results on this one were skewed because I doubt that other tables faced a 2 diamond open.
For this hand, I did not like the 2 spade bid because I thought it distorts the value of the hand. I might have doubled first and then bid the suit - after finding out something about partner's hand. It makes 5 spades - but south would like to know that north has the queen of trump.
What do you think? How should the bidding have gone to make sure we get to 4 spades.