Many years ago, when I was a mad keen learner of our beautiful game my mentor told me that, when pre-empted, you must aim for the best possible score rather than the possible best score. On that basis I X 7♠. All the erudite posturing from my fellow contributors about bidding 7NT because W won't have a ♠ to lead is all well and good, but what if s/he does! In all my years playing bridge I managed to achieve some pretty bizarre results but 7NTX -12 is not one of them, and never will be!