Two I485 Pending

XiaoBaiTu and other Experts,

所有类别排期变成当前了, 我和太太都可以递一个EB-2的I-485, 并把对方加进去

My attorney told me that "Unfortunately, you should not have two I-485 Applications pending at the same time at USCIS, as this can create major issues." Is this true?? He also mentioned as example, double finger printing may cause troubles, etc.