Posted 2010-May-05, 16:00
Double. This is analagous to 4S-X. Double is takeout oriented but you might have to double on a wide range of shapes. I would expect partner to pass with a balanced hand, bid with extreme shape, and use his jdugement on hands in between that (sometimes bidding sometimes passing).
I certainly wish this was pure takeout but I would always X with Ax Kxxx Qxx Jxxx because I have no alternative.
In general they have put a lot of pressure on you. One of you has shown some points, the other one has shown nothing, and neither of you has shown a suit. You're not going to come close to having great accuracy here. Most of the time when you have enough values you're going to double them and take a plus rather than venturing into the unknown at the 5 level.
That being said you're also unlikely to have a lot of spade values/trump tricks, so you gain by both sides being able to bid over a double, and lose little. I mean if you have QJ9x xx xxxx xxx you don't get to double, but you so rarely have that, and when you do partner often reopens X anyways.