Geez, it sounds practically impossible for an MBA to get into trading, or even structuring. From what I can tell (based on stuff here on GMATClub, WSO, and the career profiles pages at investment banks), almost all the MBAs recruited into S&T go into Sales... Are structuring and trading that off-limits for MBAs? 3underscore is really one of the chosen few, though global macroeconomic conditions are always a force to be reckoned with...
Britguy, as far as structuring goes, it sounds like in theory, an MBA should have something to contribute, but based on the info the investment banks provide, S&T almost always means "sales" for an MBA.
If I may ask, did you present your career goals as IM or structuring?