When I went through, there were two wives present out of 20 or so applicants. Only 3 ended up making it through. I thought it would be much higher based on the experience and level of preperation that I could see all had invested (most had a few hours of classic sim time and months in the books!). Post- interview I spoke with many whom were not successful, and quite a few were confused as to why. The cocktail is very pleasant, and unintimidating. I would advise the misses a semi-formal cocktail dress, perhaps nothing to low cut or low back, but all the cx brass were very cool and if she has a few questions prepared for the awkward silence she will glide right through and increase your stock! Best of luck!
NG