Deductions & credits

After reading a bunch of the various comments on this subject, i am confused with this statement saying you need to file seperately... I am reading it if one partner in the marriage doesnt meet the use test.. then you can still file jointly but only recieve the 250k exclusion and not the 500k...  

are you saying we would need to file married but seperately?  this doesnt make sense .. thx for any clarifications on this.